case study of heredity class 10

Case Study Questions Class 10 Science Heredity and Evolution

Case study questions class 10 science chapter 9 heredity and evolution.

CBSE Class 10 Case Study Questions Science Heredity and Evolution. Term 2 Important Case Study Questions for Class 10 Board Exam Students. Here we have arranged some Important Case Base Questions for students who are searching for Paragraph Based Questions Heredity and Evolution.

CBSE Case Study Questions Class 10 Science Heredity and Evolution

A scientist cross pure-bred tall (dominant) pea plant with pure-bred dwarf (recessive) pea plant he will get pea plants of F1 generation. If now self-cross the pea plant of F2 generation is done, then we obtain pea plants of F2 generation.

(a) State the type of plants not found in F2 generation but appeared in F2 generation, mentioning the reason for the same

Answer- Ratio – 3:1

(c) How does the creation of variations in a species promote survival ?

(a) Why did Mendel select a pea plant for his experiments?

Answer- Mandel Selects pea plant for his experiment, because pea plant grown easily in few days and also has some interesting characters. And also, many generations can examined by Mendel in few days or months.

Answer- Yellow pod colour and axial position are dominant traits.

Pure bred pea plant with smooth seeds (dominant characteristic) were crossed with pure bred pea plant with wrinkled seeds (recessive characteristic) . The F1 generation was self pollinated to give rise to the F2 generation.

(c) What will be the genotypic ration of F2 offspring , also mention whether it will be homozygous or heterozygous ?

Answer- Genotypic ratio = 1: 2: 1

CASE STUDY : 4

iii) What are the different methods for tracing the evolutionary relationship?

CASE STUDY : 5

The evolutionary relationships of the species we see around us. It is a sort of going backwards in time. We can do this by identifying hierarchies of characteristics between species. Similarities among organisms will allow us to group them and then study the groups. For this, which characteristics decide more fundamental differences among organisms, and which ones decide less basic differences? What is meant by ‘characteristics’, anyway? Characteristics are details of appearance or behaviour; in other words, a particular form or a particular function. That we have four limbs is thus a characteristic

ii) What are fossil?

CASE STUDY : 6

Ans: Tall and dwarf plant, round/ wrinkled seeds, white / violets flower and on the basis of pod colour etc.

Ans: Genes control traits, the diploid organism inherit two alleles from a gene i.e one is from father and one is from mother.

CASE STUDY : 7

Ans: 23 pairs in which 22 pairs are autosomal and one pair i.e 23rd pair is sex chromosome.

v) What is hermaphrodites?

CASE STUDY : 8

Ans: Geographical isolation, genetic drift, mutation and natural selection.

Leave a Reply Cancel reply

We have a strong team of experienced teachers who are here to solve all your exam preparation doubts, west bengal board class 4 maths chapter 17 solutions পেনসিল নিয়ে খেলি, rs aggarwal solutions class 5 chapter 19 parallel and perpendicular lines, ncert solutions class 3 english santoor chapter 7 the big laddoo, ncert solutions class 3 english santoor chapter 6 paper boats.

Case Study Questions Class 10 Science Chapter 9 Heredity and Evolution

• Post author: studyrate
• Post published:
• Post category: class 10th
• Post comments: 0 Comments

Case study Questions Class 10 Science Chapter 9  are very important to solve for your exam. Class 10 Science Chapter 9 Case Study Questions have been prepared for the latest exam pattern. You can check your knowledge by solving case study-based questions for Class 10 Science Chapter 9 Heredity and Evolution

Join our Telegram Channel, there you will get various e-books for CBSE 2024 Boards exams for Class 9th, 10th, 11th, and 12th.

In CBSE Class 10 Science Paper, Students will have to answer some questions based on  Assertion and Reason . There will be a few questions based on case studies and passage-based as well. In that, a paragraph will be given, and then the MCQ questions based on it will be asked.

Heredity and Evolution Case Study Questions With Answers

Here, we have provided case-based/passage-based questions for Class 10 Science  Chapter 9 Heredity and Evolution

Case Study/Passage Based Questions

Question 1:

Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from plant with wrinkled seeds. The resulting pea pod has all smooth seeds.

(i) Which of the following conclusions can be drawn? (1) The allele for smooth seeds is dominated over that of wrinkled seeds. (2) The plant with smooth seeds is heterozygous. (3) The plant with wrinkled seeds is homozygous. (a) 1 only (b) 1 and 2 only (c) 1 and 3 only (d) 1, 2 and 3

Answer: (c) 1 and 3 only

(ii) Which of the following crosses will give smooth and wrinkled seeds in same proportion? (a) RR X rr (b) Rr x rr (C) RRX Rr (d) rrrr

Answer: (b) Rr x rr

(iii) Which of the following cross can be used to determine the genotype of a plant with dominant phenotype? (a) RR RR (b) Rr x Rr (c) Rr RR (d) RR x rr

Answer: (d) RR x rr

(iv) On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F 1 generation. What will be the respective number of smooth and wrinkled seeds obtained in F 1  generation? (a) 750, 250 (b) 500, 500 (C) 800, 200 (d) 950, 50

Answer: (a) 750, 250

(v) The characters which appear in the first filial generation are called (a) recessive characters (b) dominant characters (c) lethal characters (d) non-mendelian characters.

Answer: (b) dominant characters

Question 2:

Seema crossed pure breed pea plants having round-yellow seeds with wrinkled green seeds and found that only A-B type of seeds was produced in the F1 generation. When F1 generation pea plants having A-B type of seeds were cross-breed by self-pollination, then in addition to the original round yellow and wrinkled green seeds, two new varieties A-D and C-B types of seeds were also obtained.

2.1) What are the A-B type of seeds? (a) Round -yellow (b) Round- green (c) Wrinkled- yellow (d) Wrinkled- green

Answer(a) Round -yellow

2.2) A-D are __________ and C-B are _______ type of seeds. (a) Round green and wrinkled yellow respectively (b) Wrinkled green and round yellow respectively (c) Round yellow and wrinkled green respectively (d) Wrinkled green and round green respectively

Answer(a) Round green and wrinkled yellow respectively

2.3) A and B are _____________ traits. (a) recessive (b) dominant (c) both (a) and (b) (d) None of these

Answer(b) dominant

2.4) Which one of these will be produced in maximum number in the F2 generation? (a) A-D (b) A-B (c) both (a) and (b) (d) None of these

Answer(b) A-B

2.5) The above cross is known as : (a) Test cross (b) Monohybrid cross (c) Back cross (d) Dihybrid cross

Answer(d) Dihybrid cross

Case Study 4

Purebred pea plant with smooth seeds (dominated characteristic) were crossed with a purebred pea plants with wrinkled seeds (recessive characteristic). The F1 generation was self-pollinated to give rise to the F, generation.

4.1) What is the expected observation of the F1 generation of plants? (a) 1/2 of them have smooth seeds and 1/2 of them have wrinkled seeds. (b) 1/4 of them have wrinkled seeds and 3/4 of them have smooth seeds.  (c) 3/4 of them have wrinkled seeds and 1/4 of them have smooth seeds. (d) All of them have smooth seeds. 

Answer(d) All of them have smooth seeds.

4.2) What is the expected observation of the F2 generation plants ? (a) 1/2 of them have smooth seeds and 1/2 of them have wrinkled seeds. (b) 1/4 of them have wrinkled seeds and 3/4 of them have smooth seeds. (c) 3/4 of them have wrinkled seeds and 1/4 of them have smooth seeds. (d) All of them have smooth seeds. 

Answer(b) 1/4 of them have wrinkled seeds and 3/4 of them have smooth seeds.

4.3) If a genotype consists of different types of alleles, it is called : (a) homozygous (b) heterogyzous (c) monoallelic (d) uniallelic

Answer(b) heterogyzous

4.4) The alternative form of gene is called : (a) dominant character (b) recessive character (c) alternative genes (d) allele

Answer(d) allele

4.5) Which of the following will be the genotypic ratio of the given F2 generation? (a) 1:3 (b) 3:1 (c) 1:2:1 (d) 1:1:1

Answer(c) 1:2:1

Hope the information shed above regarding Case Study and Passage Based Questions for Class 10 Science Chapter 9 Heredity and Evolution with Answers Pdf free download has been useful to an extent. If you have any other queries of CBSE Class 10 Science Heredity and Evolution Case Study and Passage Based Questions with Answers, feel free to comment below so that we can revert back to us at the earliest possible By Team Study Rate

You Might Also Like

Class 10 Maths Pair of Linear Equations in Two Variables Handwritten Notes by Toppers – Download PDF

Case study questions class 10 economics money and credit.

CBSE Class 10 Science Electricity MCQ Quiz with Answers

Leave a reply cancel reply.

Save my name, email, and website in this browser for the next time I comment.

Gurukul of Excellence

Classes for Physics, Chemistry and Mathematics by IITians

Join our Telegram Channel for Free PDF Download

Case Study and Passage Based Questions for Class 10 Science Chapter 9 Heredity and Evolution

• Last modified on: 3 years ago
• Reading Time: 5 Minutes

In CBSE Class 10 Science Paper, Students will have to answer some questions based on Assertion and Reason . There will be a few questions based on case studies and passage based as well. In that, a paragraph will be given, and then the MCQ questions based on it will be asked.

Here, we have provided case based/passage based questions for Class 10 Science Chapter 9 Heredity and Evolution .

Case Study/Passage Based Questions

Question 1:

Read the following and answer any four questions from (i) to (v).

Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from plant with wrinkled seeds. The resulting pea pod has all smooth seeds.

(i) Which of the following conclusions can be drawn? (1) The allele for smooth seeds is dominated over that of wrinkled seeds. (2) The plant with smooth seeds is heterozygous. (3) The plant with wrinkled seeds is homozygous. (a) 1 only (b) 1 and 2 only (c) 1 and 3 only (d) 1, 2 and 3

(ii) Which of the following crosses will give smooth and wrinkled seeds in same proportion? (a) RR X rr (b) Rr x rr (C) RRX Rr (d) rrrr

(iii) Which of the following cross can be used to determine the genotype of a plant with dominant phenotype? (a) RR RR (b) Rr x Rr (c) Rr RR (d) RR x rr

(iv) On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F 1 generation. What will be the respective number of smooth and wrinkled seeds obtained in F 1 generation? (a) 750, 250 (b) 500, 500 (C) 800, 200 (d) 950, 50

(v) The characters which appear in the first filial generation are called (a) recessive characters (b) dominant characters (c) lethal characters (d) non-mendelian characters.

Download CBSE Books

Exam Special Series:

• Sample Question Paper for CBSE Class 10 Science (for 2024)
• Sample Question Paper for CBSE Class 10 Maths (for 2024)
• CBSE Most Repeated Questions for Class 10 Science Board Exams
• CBSE Important Diagram Based Questions Class 10 Physics Board Exams
• CBSE Important Numericals Class 10 Physics Board Exams
• CBSE Practical Based Questions for Class 10 Science Board Exams
• CBSE Important “Differentiate Between” Based Questions Class 10 Social Science
• Sample Question Papers for CBSE Class 12 Physics (for 2024)
• Sample Question Papers for CBSE Class 12 Chemistry (for 2024)
• Sample Question Papers for CBSE Class 12 Maths (for 2024)
• Sample Question Papers for CBSE Class 12 Biology (for 2024)
• CBSE Important Diagrams & Graphs Asked in Board Exams Class 12 Physics
• Master Organic Conversions CBSE Class 12 Chemistry Board Exams
• CBSE Important Numericals Class 12 Physics Board Exams
• CBSE Important Definitions Class 12 Physics Board Exams
• CBSE Important Laws & Principles Class 12 Physics Board Exams
• 10 Years CBSE Class 12 Chemistry Previous Year-Wise Solved Papers (2023-2024)
• 10 Years CBSE Class 12 Physics Previous Year-Wise Solved Papers (2023-2024)
• 10 Years CBSE Class 12 Maths Previous Year-Wise Solved Papers (2023-2024)
• 10 Years CBSE Class 12 Biology Previous Year-Wise Solved Papers (2023-2024)
• ICSE Important Numericals Class 10 Physics BOARD Exams (215 Numericals)
• ICSE Important Figure Based Questions Class 10 Physics BOARD Exams (230 Questions)
• ICSE Mole Concept and Stoichiometry Numericals Class 10 Chemistry (65 Numericals)
• ICSE Reasoning Based Questions Class 10 Chemistry BOARD Exams (150 Qs)
• ICSE Important Functions and Locations Based Questions Class 10 Biology
• ICSE Reasoning Based Questions Class 10 Biology BOARD Exams (100 Qs)

✨ Join our Online NEET Test Series for 499/- Only for 1 Year

Leave a Reply Cancel reply

Editable Study Materials for Your Institute - CBSE, ICSE, State Boards (Maharashtra & Karnataka), JEE, NEET, FOUNDATION, OLYMPIADS, PPTs

Discover more from Gurukul of Excellence

Subscribe now to keep reading and get access to the full archive.

Type your email…

Continue reading

• New QB365-SLMS
• 12th Standard Materials
• 11th Standard Materials
• 10th Standard Materials
• 9th Standard Materials
• 8th Standard Materials
• 7th Standard Materials
• 6th Standard Materials
• 12th Standard CBSE Materials
• 11th Standard CBSE Materials
• 10th Standard CBSE Materials
• 9th Standard CBSE Materials
• 8th Standard CBSE Materials
• 7th Standard CBSE Materials
• 6th Standard CBSE Materials
• Tamilnadu Stateboard
• Scholarship Exams
• Scholarships

CBSE 10th Standard Science Subject Heredity and Evolution Chapter Case Study Questions With Solution 2021

By QB365 on 21 May, 2021

QB365 Provides the updated CASE Study Questions for Class 10 , and also provide the detail solution for each and every case study questions . Case study questions are latest updated question pattern from NCERT, QB365 will helps to get  more marks in Exams 

QB365 - Question Bank Software

Cbse 10th standard science subject heredity and evolution case study questions with solution 2021.

10th Standard CBSE

Final Semester - June 2015

Sex determination is the method by which distinction between males and females is established in a species. The sex of an individual is determined by specific chromosomes. These chromosomes are called sex chromosomes or allosomes. X and Y chromosomes are called sex chromosomes. The normal chromosomes other than the sex chromosomes of an individual are known as autosomes. (i) In XX-XO type of sex determination (a) females produce two different types of gametes (b) males produce two different types of gametes (c) females produce gametes with Y chromosome (d) males produce gametes with Y chromosome. (ii) A couple has six daughters. What is the possibility of their having a girl next time?

(iii) Number of autosomes present in liver cells of a human female is

(iv) XX-XO type of sex determination and XX-XY type of sex determination are the examples of

(v) Select the incorrect statement. (a) In male grasshoppers, 50% of sperms have no sex chromosome (b) Female fruitfly is heterogametic (c) Human male produces two types of sperms 50% having X chromosome and 50% having Y chromosomes (d) In turtle, sex determination is regulated by environmental factors.

Gregor Mendel conducted hybridisation experiments on garden peas for seven years and proposed the laws of inheritance in living organisms. He investigated characters in the garden pea plant that were manifested as two opposing traits, e.g., tall or dwarf plants, yellow and green seeds, etc. (i) Among the seven pairs of contrasting traits in pea plant as studied by Mendel, the number of traits related to flower, pod and seed respectively were

(ii) The colour based contrasting traits in seven contrasting pairs, studied by Mendel in pea plant were

(iii) Refer to the given table of contrasting traits in pea plants studied by Mendel.

Which of the given traits is correctly placed? (a) (i), (ii) and (iii) only (b) (ii), (iii) and (iv) only (c) (ii) and (iii) only (d) (i), (ii), (iii) and (iv) (iv) Some of the dominant traits studied by Mendel were (a) round seed shape, green seed colour and axial flower position (b) terminal flower position, green pod colour and inflated pod shape (c) violet flower colour, green pod colour and round seed shape (d) wrinkled seed shape, yellow pod colour and axial flower position. (v) Which of the following characters was not chosen by Mendel?

Mendel crossed tall and dwarf pea plants to study the inheritance of one gene. He collected the seeds produced as a result of this cross and grew them to generate plants of the first hybrid generation which is called the first filial progeny or F 1 : Mendel then self pollinated the tall F 1 plants and he obtained F 2 generation. (i) In garden pea, round shape of seeds is dominant over wrinkled shape. A pea plant heterozygous for round shape of seed is selfed and 1600 seeds produced during the cross are subsequently germinated. How many seedlings would have non-parental phenotype?

(ii) If 'A' represents the dominant gene and 'a' represents its recessive allele, which of the following would be the most likely result in the first generation offspring when Aa is crossed with aa ? (a) All will exhibit dominant phenotype. (b) All will exhibit recessive phenotype. (c) Dominant and recessive phenotypes will be 50% each. (d) Dominant phenotype will be 75%. (iii) Which of the following crosses will give tall and dwarf pea plants in same proportions?

(iv) What result Mendel would have got, if he self pollinated a homozygous tall F 2 plant? (a) TT and Tt (b) All Tt (c) All TT (d) All tt (v) In plant, tall phenotype is dominant over dwarf phenotype, and the alleles are designated as T and t, respectively. Upon crossing one tall and one dwarf plant, total 250 plants were obtained, out of which 124 displayed tall phenotype and rest were dwarf. Thus, the genotype of the parent plants were (a) TT x TT (b) TT x tt (c) Tt x Tt d) Tt x tt.

The cross that include the inheritance of two pairs of contrasting characters simultaneously is referred as dihybrid cross. Mendel chose pure breeding plants for yellow and green seeds and round and wrinkled shape of seeds. He cross pollinated the plant having yellow round seeds with plant having green wrinkled seeds. All the plants produced in F 1 generation were having, yellow round seeds. The plants raised from these seeds were self pollinated, that resulted in production of plants having four phenotypically different types of seeds. (i) When a cross is made between a yellow round seeded plant (YyRr) and a yellow wrinkled seeded plant (Yyrr), what is true regarding the proportions of phenotypes of the offsprings in F 1  generation?

(ii) How many types of gametes can be produced by YYrr?

(iii) In Mendelian dihybrid cross, when heterozygous tall plant with green seeds are self crossed the progenies are

(iv) When round yellow seeded heterozygous pea plants are self fertilised, the frequency of occurrence of RrYY genotype among the offsprings is

(v) The percentage of yr gamete produced by YyRr parent will be

In human, the allele for brown eyes (B) is dominant over that for blue eyes (b). A brown eyed woman marries a blue eyed man, and they have six children. Four of the children are brown eyed and two of them are blue eyed. (i) What is the genotype of blue eyed offspring?

(ii) What is the woman's genotype?

(iii) The ovum, produced by the mother carries the gene regarding eye colour is

(iv) The ratio of brown eyed children to blue eyed children in this family is 2 : 1, which deviates from typical phenotypic ratios for monohybrid inheritance. What might be the reason? (a) Gametes carrying the brown eyed allele are more viable then those with the blue eyed allele. (b) A different pattern of inheritance other than monohybrid inheritance is involved. (c) Not all of their babies survived childbirth, thus causing a distortion in the actual ratio. (d) The actual ratio differs from the expected ratio because the sample size is too small. (v) What is the gene carried by of the man's sperm regarding the eye colour?

*****************************************

Cbse 10th standard science subject heredity and evolution case study questions with solution 2021 answer keys.

(i) (b) : In XX-XO type and XX-XY type of sex determining mechanisms, males produce two different types of gametes, either with or without X-chromosome (XO type), or some gametes with X-chromosome and some with Y-chromosome (XY type). Such type of sex determination mechanism is designated to be the example of male heterogamety. In both, females are homogametic and produce X type of gametes in both the cases and have XX genotype. (ii) (b): The possibility of having a girl or boy child is equal i.e., 50%, as 50% male gametes are Y type and 50% are X type. Fusion of egg with X type sperm will produce a girl child. (iii) (b): In humans, number of autosomes are 2n = 44 or 22 pairs regardless of the sex. (iv) (a):  In XX-XO type and XX-XY type of sex determining mechanisms, males produce two different types of gametes, either with or without X-chromosome (XO type), or some gametes with X-chromosome and some with Y-chromosome (XY type). Such type of sex determination mechanism is designated to be the example of male heterogamety. In both, females are homogametic and produce X type of gametes in both the cases and have XX genotype. (v) (b): Male fruitfly is heterogametic whereas female fruitfly is homogametic.

(i) (a) : Characters studied by Mendel are as follows:

Phenotypic ratio is: 

(i) (c) (ii) (b) : According to the given passage some children show recessive trait, i.e., homozygous. So, the woman must be heterozygous. (iii) (c): Human ova are haploid, hence they only contain one copy of each gene. Since the woman has a Bb genotype her ova would contain either B or b allele. (iv) (d): According to the given passage, within a single family, the sample size of offspring in each generation is very small. Hence, the actual phenotypic and genotypic ratios often deviate from expected ratios. It is only when sample sizes of offspring is large that actual ratios approach theoretical or expected ratios more closely. (v) (c) : Human sperm is haploid, hence they only contain one copy of each gene. Since the man has a bb genotype, his sperm would contain allele b only.

Related 10th Standard CBSE Science Materials

10th standard cbse syllabus & materials, cbse 10th maths probability chapter case study question with answers, cbse 10th maths statistics chapter case study question with answers, cbse 10th maths surface areas and volumes chapter case study question with answers, cbse 10th maths areas related to circles chapter case study question with answers, cbse 10th maths circles chapter case study question with answers, cbse 10th maths some applications of trigonometry chapter case study question with answers, cbse 10th maths introduction to trigonometry chapter case study question with answers, cbse 10th maths coordinate geometry chapter case study question with answers, cbse 10th maths triangles chapter case study question with answers, cbse 10th maths arithmetic progressions chapter case study questions with answers, cbse 10th maths quadratic equations chapter case study questions with answers, cbse 10th social science the making of a global world chapter case study question with answers, cbse 10th social science nationalism in india chapter case study question with answers, cbse 10th social science the rise of nationalism in europe chapter case study question with answers, cbse 10th maths pair of linear equation in two variables chapter case study question with answers.

Class VI to XII

Tn state board / cbse, 3000+ q&a's per subject, score high marks.

10th Standard CBSE Study Materials

10th Standard CBSE Subjects

CBSE NCERT Solutions

NCERT and CBSE Solutions for free

Case Study Chapter 9 Heredity And Evolution

Please refer to Chapter 9 Heredity And Evolution Case Study Questions with answers provided below. We have provided Case Study Questions for Class 10 Science for all chapters as per CBSE, NCERT and KVS examination guidelines. These case based questions are expected to come in your exams this year. Please practise these case study based Class 10 Science Questions and answers to get more marks in examinations.

Case Study Questions Chapter 9 Heredity And Evolution

Case/Passage – 1

Question: A person first crossed pure-breed pea plants having roundyellow seeds with pure-breed pea plants having wrinkledgreen seeds and found that only A-B type of seeds were produced in the F1 generation. When F1 generation pea plants having A-B type of seeds were cross-breed by selfpollination, then in addition to the original round-yellow and wrinkled-green seeds, two new varieties A-D and C-B type of seeds were also obtained. (a) What are A-B type of seeds? (b) State whether A and B are dominant traits or recessive traits. (c) What are A-D type of seeds? (d) What are C-B type of seeds? (e) Out of A-B and A-D types of seeds, which one will be produced in (i) minimum numbers, and (ii) maximum numbers, in the F 2  generation?

(a) Round yellow (b) A (round) and B (yellow) are dominant traits (c) Round-green (d) Wrinkled-yellow (e) (i) A–D (ii) A–B

Question: Question number (a) – (d) are based on the images (A) and (B) given below. Study them and answer the following questions.  

(a) What term can be used for the structure given in image A? (b) What term can be used for the structure given in image B? (c) Which image shows a common ancestry?  (d) Which image has a common function but different origin?   

(a) Homologous organs (b) Analogous organs (c) Image A shows common ancestry (d) Image B i.e., analogous organs have a different origin but common functions.

Case/Passage – 2

Most human chromosomes have a maternal and a paternal copy, and we have 22 such pairs. But one pair, called the sex chromosomes, is odd in not always being a perfect pair. Women have a perfect pair of sex chromosomes, both called X. But men have a mismatched pair in which one is a normal-sized X while the other is a short one called Y. So women are XX, while men are XY

Question: If a normal cell of human body contains 46 pairs of chromosomes then the numbers of chromosomes in a sex cell of a human being is most likely to be: (a) 60 (b) 23 (c) 22 (d) 40   

Question: The process where characteristics are transmitted from parent to offsprings is called: (a) Variation (b) Heredity (c) Gene (d) Allele (e) None of the above   

Question: In human males, all the chromosomes are paired perfectly except one. These unpaired chromosomes are: (a) Large chromosome (b) Small chromosome (c) Y chromosome (d) X chromosome 

Question: Which of the following determines the sex of a child? (a) The length of the mother’s pregnancy (b) The length of time between ovulation and copulation (c) The presence of an X chromosome in an ovum (d) The presence of a Y chromosome in a sperm 

Question:Who have a perfect pair of sex chromosomes? (a) Girls only (b) Boys only (c) Both girls and boys (d) It depends on many other factors   

Case/Passage – 3

In some animals, the temperature at which fertilised eggs are kept determines whether the animal developing in the egg will be male or female. In other animals, such as snails, individuals can change sex, that is sex is not genetically determined. In human beings, sex of individuals is largely genetically determined. All chromosomes in human beings are not paired. We have 22 pairs and one pair of sex chromosomes which is odd and not always a perfect pair.

Question. Who is responsible for birth of male child? (a) Father (b) Mother (c) Father only in first pregnancy. (d) Mother only in first pregnancy

Question. How many pairs of chromosomes are called autosomes? (a) 23 (b) 22 (c) 21 (d) 20

Question. Which pair of chromosomes are present in Male (a) XX (b) YY (c) XY (d) XXY

Question. Which of the following statement is true? (a) Men have short sized X chromosome (b) Men have one long sized Y chromosome (c) Men have normal sized Y chromosome (d) Men have one short sized Y chromosome

Question. Which pair of chromosomes are present in female? (a) XX (b) YY (c) XY (d) XXY

Related Posts

Gender, Religion and Caste Class 10 Social Science Notes and Questions

A Horse and Two Goats Summary by RK Narayan

Life Processes Class 10 Science Notes And Questions

CBSE Expert

Class 10 Science: Case Study Chapter 9 Heredity and Evolution PDF Download

In CBSE Class 10 Science Paper, Students will have to answer some questions based on  Assertion and Reason . There will be a few questions based on case studies and passage-based as well. In that, a paragraph will be given.

Here we are providing you with Class 10 Science Chapter 9 Heredity and Evolution Case Study Questions, by practicing these Case Study and Passage Based Questions will help you in your Class 10th Board Exam.

Case Study Chapter 9 Heredity and Evolution

Here, we have provided case-based/passage-based questions for Class 10 Science  Chapter 9 Heredity and Evolution

Case Study/Passage Based Questions

Question 1:

Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from plant with wrinkled seeds. The resulting pea pod has all smooth seeds.

(i) Which of the following conclusions can be drawn? (1) The allele for smooth seeds is dominated over that of wrinkled seeds. (2) The plant with smooth seeds is heterozygous. (3) The plant with wrinkled seeds is homozygous. (a) 1 only (b) 1 and 2 only (c) 1 and 3 only (d) 1, 2 and 3

Answer: (c) 1 and 3 only

(ii) Which of the following crosses will give smooth and wrinkled seeds in same proportion? (a) RR X rr (b) Rr x rr (C) RRX Rr (d) rrrr

Answer: (b) Rr x rr

(iii) Which of the following cross can be used to determine the genotype of a plant with dominant phenotype? (a) RR RR (b) Rr x Rr (c) Rr RR (d) RR x rr

Answer: (d) RR x rr

(iv) On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F 1 generation. What will be the respective number of smooth and wrinkled seeds obtained in F 1  generation? (a) 750, 250 (b) 500, 500 (C) 800, 200 (d) 950, 50

Answer: (a) 750, 250

(v) The characters which appear in the first filial generation are called (a) recessive characters (b) dominant characters (c) lethal characters (d) non-mendelian characters.

Answer: (b) dominant characters

Question 2:

Seema crossed pure breed pea plants having round-yellow seeds with wrinkled green seeds and found that only A-B type of seeds was produced in the F1 generation. When F1 generation pea plants having A-B type of seeds were cross-breed by self-pollination, then in addition to the original round yellow and wrinkled green seeds, two new varieties A-D and C-B types of seeds were also obtained.

2.1) What are the A-B type of seeds? (a) Round -yellow (b) Round- green (c) Wrinkled- yellow (d) Wrinkled- green

Answer(a) Round -yellow

2.2) A-D are __________ and C-B are _______ type of seeds. (a) Round green and wrinkled yellow respectively (b) Wrinkled green and round yellow respectively (c) Round yellow and wrinkled green respectively (d) Wrinkled green and round green respectively

Answer(a) Round green and wrinkled yellow respectively

2.3) A and B are _____________ traits. (a) recessive (b) dominant (c) both (a) and (b) (d) None of these

Answer(b) dominant

2.4) Which one of these will be produced in maximum number in the F2 generation? (a) A-D (b) A-B (c) both (a) and (b) (d) None of these

Answer(b) A-B

2.5) The above cross is known as : (a) Test cross (b) Monohybrid cross (c) Back cross (d) Dihybrid cross

Answer(d) Dihybrid cross

You can also practice Class 10 Science MCQ Questions for Board Exams.

Leave a Comment Cancel reply

Save my name, email, and website in this browser for the next time I comment.

Download India's best Exam Preparation App Now.

Key Features

• Revision Notes
• Important Questions
• Previous Years Questions
• Case-Based Questions
• Assertion and Reason Questions

No thanks, I’m not interested!

Talk to our experts

1800-120-456-456

NCERT Solutions for Class 10 Science Chapter 8 Heredity and Evolution

• NCERT Solutions
• Chapter 9 Heredity And Evolution

Heredity and Evolution Class 10 NCERT Solutions FREE PDF Download

Understanding heredity and evolution is fundamental to grasping the principles of biology. Class 10 Science Chapter 8 NCERT explores these concepts in depth, covering the mechanisms of inheritance, the laws formulated by Gregor Mendel, and the significance of variations in evolution. It delves into the structure of DNA, the process of natural selection, and the evolutionary relationships among organisms. Our FREE PDF download of the NCERT solutions for class 10 science provides detailed explanations, illustrative diagrams, and answers to all exercises. It is an essential resource for students aiming to excel in their exams.

Download the FREE PDF of Class 10 NCERT Solutions for Heredity and Evolution prepared by master teachers. Solutions are prepared according to the CBSE Science class 10 syllabus and exam pattern for 2024-25 by Vedantu Master Teachers.

Quick Insights of Heredity and Evolution Class 10 NCERT Solutions

Heredity class 10 questions and answers will give you insights into the General Introduction: Principles governing the transmission of characters from one generation to another and also explain the genetic makeup and diversity observed within species.

Heredity class 10, the section will give you a clear understanding of the mechanisms by which traits are inherited and expressed and the difference between dominant and recessive traits.

The understanding of topics like The fascinating experiment of Gregor Mendel, known as the "Father of Genetics," and his trials with pea plants led to the discovery of fundamental laws of inheritance.

These solutions can help students analyse their preparation and understanding of concepts.

Class 10 Science Chapter 8 question answer NCERT solutions topics are included according to the revised academic year 2024-25 syllabus.

Access NCERT Solutions for Class 10 Biology Chapter 8 -Heredity and Evolution

1. If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Ans: Asexual reproduction requires the involvement of a single parent and does not involve the fusion of haploid gametes. In this, the offspring produced are identical to the parents i.e., they are a nearly exact copy of their parents DNA. However, sometimes, copying of DNA is similar but not identical to the original which leads to change in variations. Hence, the newly formed DNA has some variations giving rise to a new trait. Thus, future generations inherit this trait and successive generations keep accumulating variations. Thus, if 10% of the population exists in trait A and 60% of the same population exists in trait B, it can be concluded that trait B has arisen earlier because the trait continued to replicate and exist in a higher percentage of the population.

2. How does the creation of variations in a species promote survival?

Ans: In any circumstances, species get adapted to survive in a particular habitat. Sometimes, the habitat gets disturbed due to drastic changes in the environment and proves fatal for certain species. For example, many microorganisms inhabit freshwater ponds. The bacteria living in freshwater will get killed if there is a sudden temperature rise. it. However, some of the species will be able to survive in the heat of those who are resistant to it. These species will survive and reproduce within the changing environment. If there have been no heat-resistant variants, the whole species of bacteria would be extinct. Hence, the survival of species is promoted. 

1. How do Mendel’s experiments show that traits may be dominant or recessive?

Ans: Mendel began his genetic experiment on pea plants in 1856 with a single character (with two alternative traits) called a monohybrid cross. The crossing was done between true-breeding tall plants (TT) and true breeding dwarf plants. In the first filial generation, he received only tall plants, no dwarf trait was seen. Now, Self-pollination of the F1 progeny was done which resulted in both tall and dwarf plants. Based on the monohybrid cross, Mendel’s conclusion was made that out of the two traits of a character, one is dominant and the other is recessive. The dominant trait is an allele that always expresses itself externally while the expression of the recessive trait is masked in the presence of the dominant trait when present in homozygous or heterozygous conditions. Thus, the recessive trait is expressed only in homozygous conditions. Eventually, the tall plants present in F1 were not true-breeding. They were heterozygous (Tt) tall plants. Hence, the expression of the recessive allele (t) gets suppressed by the dominant allele.

2. How do Mendel’s experiments show that traits are inherited independently?

Ans: Mendel directed his attention to two pairs of contrasting characters. The cross which involves two pairs of alleles is known as a dihybrid cross. He did a hybrid cross on pea, taking two characters at a time. His dihybrid cross demonstrated an independent assortment of genes. Mendel chose seed colour and seed shape as the two characters for his experiment. Mendel crossed round and yellow seeds (RRYY) with wrinkled and green seeds (rryy) (parental generation). First filial generation (F1) showed all round and yellow seeds (law of dominance) since round seed shape is dominant over wrinkled seed shape and yellow seed colour is dominant over green seed colour.

Self-pollination is the F1 generation that resulted in the F2 generation that showed a variety of seeds. In F2 progeny the yellow round seeds, green round seeds, yellow wrinkled seeds, and green wrinkled seeds were seen in the ratio of 9:3:3:1.

The F2 generation had two new variants of seeds - round green and yellow wrinkled (different from the parental types). Thus, the conclusion can be made that the genes for the two characters are assorted independently.

3. A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits − blood group A or O − is dominant? Why or why not?

Ans: No, the given information is not enough to tell whether which of the traits is dominant, either A or O.

Blood groups are inherited from our biological parents. It has three alleles A, B and O. This can be explained via two cases:

When A is dominant and O is recessive

Combination of man can be I A I A Or I A I O

A combination of women will be I O I O

The blood group of a child is A when A is dominant and father is pure I A I A but the Blood group of children if the father is I A I O :

Here 50% of the progeny is blood group A while 50% has blood group O when the father is heterozygous I A I O.

When A is recessive and O is dominant  Combination of father - I A I A

Combination of the mother can be I A I O OR I O I O Blood group of the child when a mother is I A I O :

Here also 50% of the progeny has blood group A while 50% Of them has blood group O. The blood group of the child would have been O, mother was homozygous I O I O .

From the above cases, we conclude that the blood group of the child will be O if any of the characters are dominant. Thus, it is difficult to determine the dominant character. 

4. How is the sex of the child determined in human beings?

Ans: In human beings, the sex of the child is determined by the chromosomal combination of parents. An ideal pair of sex chromosomes i.e. XX is seen in women, and a mismatched pair i.e. XY is seen in men. The eggs produced in females will carry the X chromosome and half of the sperms will carry the Y chromosome and the other half will carry the X chromosome in the case of males. Now, when fertilization is done between them, two cases can be considered:

Case 1:  when the egg fuses with a sperm carrying the Y chromosome, the child will be a boy.

Case 2: when the egg fuses with a sperm carrying an X chromosome, the offspring will be a girl.

Parents$\quad\quad$XX (Female)$\quad\quad$XY(Male)

$\quad\downarrow$

$\quad\quad\quad\quad\quad\quad\quad\quad\quad \downarrow$ 

Gametes$\quad\quad$  X $\quad\quad\quad\quad\quad$  XY

1. What are the different ways in which individuals with a particular trait may increase in a population?

Ans: The different ways mentioned are:

I.  Natural selection – Certain variations give a survival advantage to individuals in a population in a changing environment increasing their population. Natural selection fits individuals having better adaptability.

II.  Genetic drift: An increase of certain individuals is seen in a population even if they give no survival advantage in case of Accidents in small populations.

III.  There are cases in which some traits are not inherited but acquired by an individual during its lifetime. The acquired characters help the individual to survive better and increase its population.

2. Why are traits acquired during the lifetime of an individual not inherited? 

Ans : In the case of reproduction, Progeny receives the germ cells from the parent. So, any changes within the germ cells (leading to variation or new traits) are inherited by the progeny. Some traits are acquired by an individual during its lifetime due to environmental influences or other external factors. An acquired trait involves changes in non-reproductive tissues (somatic cells). Thus, these traits cannot be inherited because acquired traits do not involve changes in the germ cells.

3. Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics? 

Ans: Fewer variations will be accumulated by species of small populations. When such a species reproduces, there are fewer chances of having progeny with some useful variations (that will give a better survival advantage). Thus, in case of disease, they will not be able to survive. Extinction will take place and the genes will be lost forever.

1. What factors could lead to the rise of a new species? 

Ans: The one or more new species formed from an existing species by evolutionary means is called speciation. Factors leading to the formation of new species are:

(i)  Genetic drift

(ii)  Natural selection

(iii)  Severe DNA change.

(iv)  Reproductive isolation.

2.  Will geographical isolation be a major factor in the speciation of self-pollinating plant species? Why or why not?

Ans: Geographical isolation helps in the prevention of the transfer of genes between two species. In a self-pollinating plant, pollen is transferred from the anther of one flower to the stigma of the same flower or another flower of the same plant. No external agent is required for pollination, neither is it dependent on another plant for pollination. So, geographical isolation cannot affect the species and cannot be affected by geographical isolation in self-pollinating plants.

3. Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually? Why or why not?

Ans: Geographical isolation helps in the prevention of the transfer of genes (gene flow) between populations of a species. In asexual reproduction, A single organism can give rise to new individuals. When there is an error during the copying of DNA, variation occurs in these reproducing organisms. Therefore, the formation of new species cannot be affected by geographical isolation in an asexually reproducing organism.

1. Give an example of characteristics being used to determine how close two species are in evolutionary terms.

 Ans: Evolutionary relationships in organisms can be traced by similarities in characteristics. Few characteristics In different organisms, few of the characters are similar as they are inherited from a common ancestor. And a link is created between different stages of the evolution of species. Feathers were also present on dinosaurs that are seen on birds today. However, feathers were not used by dinosaurs to fly but as insulation. Later birds seemed to adapt the feathers for flight. Thus, this is an indication that birds are very closely related to reptiles since dinosaurs were reptiles. This also proves that reptiles and birds are closely related and that the evolution of wings started in reptiles.

2. Can the wing of a butterfly and the wing of a bat be considered homologous organs? 

Ans: The organs having the same fundamental structure but different functions are called homologous organs . For example, the wings of a butterfly and the wings of a bat are not homologous organs as they do not have the same origin or the same basic structure. The wings of a butterfly and the wings of a bat are analogous organs as they perform the same function of flight even though their origin and structure are different.

3. What are fossils? What do they tell us about the process of evolution? 

Ans: Fossils are the remains or imprints of hard parts of the animals like skeletal structures. These structures were once inhabited on earth. Fossils provide one of the most acceptable pieces of evidence in support of evolution because we can study the evolutionary past of organisms in the form of their fossils. By studying the fossils, the changes can be identified that had occurred in these organisms to give rise to the present-day forms. Thus, a connecting link is observed between the organisms of the past and the organisms of the present.

1. Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species?

Ans: A species is a group of interbreeding individuals. are all the Observable features of human beings like  Skin colour, looks, and size are generally environmentally controlled. Thus, various human races are formed based on these features. However, all human beings are capable of reproducing with each other and producing offspring irrespective of skin colour, height, language, race etc. Therefore, all human beings belong to one species, Homo sapiens.

2. In evolutionary terms, can we say which among bacteria, spiders, fish and chimpanzees have a ‘better’ body design? Why or why not?

Ans: In evolutionary terms, it is difficult to say that among bacteria, spiders, fish and chimpanzees which has a ‘better’ body design as it involves the development of the most efficient and appropriate features in a body design for survival and adaptation. One of the examples is, organisms having a complex body design face several difficulties while surviving in particular situations whereas, organisms with the simplest body design like bacteria can survive in extreme habitats. Thus, Evolution only leads to the development of complex body designs and it cannot be equated with progress.

1. A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as

(a)  TTWW

(b)  TTww

(c)  TtWW

(d)  TtWw

Ans: (c) There are two flower colours violet and white but F1 showed only violet flowers which means that violet flower colour (V) is the dominant trait that masks the recessive trait (v) (white flower colour). The F1 progeny had half tall and half short plants. Thus, both dominant and recessive traits are expressed in the F1 progeny. So, it can be said that the tall plants were not true-breeding and must be genetically heterozygous for the character height (Tt). Hence, the genetic make-up of the tall parent can be represented as TtVV. Therefore, the cross involved in the given question is:

TtVV × ttvv

$\downarrow$

TtVv − ttVv

Therefore, half the progeny is tall, but all of them have violet flowers.

2. An example of homologous organs is

our arm and dog’s fore-leg

our teeth and an elephant’s tusks

potato and runners of grass

all the above

Ans: (d) All of the Above.

In all the examples mentioned above, the basic internal structure and origin of the organs are the same but their functions are different. Thus, it is called a homologous organ. For example, an elephant's tusk is considered to be a modified incisor hence, it has the same origin but different function. Tubers of potato and grass runners are both stem modifications but differ in function, hence these are homologous organs.

3. In evolutionary terms, we have more in common with

 (a)  a Chinese schoolboy.

 (b)  a chimpanzee.

 (c)  a spider.

 (d) a bacterium

Ans. (a) In evolutionary terms, we have more in common with a Chinese schoolboy. As, both belong to the same species, Homo sapiens. Chimpanzees and humans are two different species having a common ancestor.

4. A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?

Ans: Children with light-coloured eyes can either have LL or Ll or ll genotypes. An assumption can be taken that the children have LL (both dominant alleles) genotype. This can be only when both the parents are also of the LL  genotype.

LL$\quad\quad\times\quad\quad$LL

$\quad\quad\quad\downarrow$

$\quad\quad\quad$LL

If ll genotype is present in children with light-coloured eyes, then their parents will also have ll genotype.

ll$\quad\quad\times\quad\quad$ll

$\quad\quad\quad$ll

Therefore, it would be difficult to conclude whether light eye colour is dominant or recessive.

5. How are the areas of study − evolution and classification − interlinked?

Ans: Classification is the process by which scientists group two living organisms based on their similarities. Those species that have more characteristics in common are closely related. And if two species are more closely related, which means they have a more recent ancestor.

For example, in a family, brothers and sisters are more closely related than their cousins. So, we can say that brother and sister have recent common ancestors i.e., their parents. The common ancestors for brother, sister and cousin are their grandparents. Due to sexual reproduction, there is an accumulation of variation over generations which leads to the creation of different phenotypes and genotypes as we move down a family (evolution) tree.

6. Explain the terms analogous and homologous organs with examples. Solution 6:

Homologous organs are similar in origin (or are embryologically similar) but perform different functions. Forelimbs of frogs, lizards, pigeons, bats, whales, horses and humans have the same basic structural plan but different functions. For example, the wings help in flight whereas the human forearm helps in various activities.

Ans: The organs having similar functions, different structural details and origin are called analogous organs. For example, the wings of a bird and a bat are similar in function, but the similarity does not signify that these animals are more closely related. The general structure of the wings of insects is different from that of a bird and a bat but have a similar. Also, when carefully observed, we find that the wings of a bat are just the folds of skin that are stretched between its fingers whereas the wings of birds are present all along the arm. Likewise, the fins of fishes and flippers of whales are also examples of analogous organs. Therefore, these organs are analogous.

7. Outline a project which aims to find the dominant coat colour in dogs. 

Ans: There are a variety of genes present in dogs that govern coat colour. At least eleven identified gene series (A, B, C, D, E, F, G, M, P, S, T) are present that influence coat colour in dogs.

One gene from each of its parents is inherited by the dog. The dominant gene gets expressed in the phenotype. For example, If, the “B” gene is inherited by a dog, it can be genetically either black or brown. Let us assume that :

(i) one parent is homozygous black (BB),

(ii) the other parent is homozygous brown (bb).

                                     BB

Since. Thus, the phenotype is black as black (B) is dominant so, all the offspring are black i.e. However, genotypically they are heterozygous for the B allele (Bb). That is all offspring are heterozygous black.

If the F1 heterozygous pups are crossed, they will produce 25% homozygous black (BB), 50%   heterozygous black (Bb), and 25% homozygous brown (bb) offspring.

8. Explain the importance of fossils in deciding evolutionary relationships. 

Ans: Remains of the organism that once existed on earth are called fossils. They represent the ancestors of the plants and animals that are alive today are represented by fossils. They get buried under the layers of earth, mud and silt and remain preserved for millions of years. When an animal dies and gets buried, fossils are formed. The soft tissue of an individual quickly decomposes leaving the hard bones or shells behind. Further, the sediment builds over and hardens into rock. Thus by digging, we can find that the fossils which are closer to the surface are more recent than the fossils we find in deeper layers.

Let us start 100 million years ago. Few invertebrates on the sea-bed die are buried in the sand. Sandstones are formed under pressure by the accumulation of sands. After millions of years, dinosaurs living in the area die, and their bodies, too, are buried in mud. The mud gets compressed into rock, above the rock containing the earlier invertebrate fossils. Further, millions of years later, some horse-like creatures died in that area and got fossilized in rocks above the dinosaur fossils. In the next coming years, the bodies of horse-like creatures dying in the area are fossilised in rocks above these earlier rocks. Dinosaur and invertebrate fossils can also be found when the area is excavated deeper. Thus, scientists can easily predict that horse-like animals evolved later than the dinosaurs and the invertebrates by digging that area. Thus, from the above example, it can be concluded that the fossils found closer to the surface of the earth are more recent than the fossils present in deeper layers.

Layers of fossils

9. What evidence do we have for the origin of life from inanimate matter?  

Ans: An experiment was conducted in 1953 by Stanley L. Miller and Harold C. Urey to understand the origin of life on the earth. It was suggested by J.B.S. Haldane that life originated from simple inorganic molecules. According to him, when the earth was formed, it was a hot gaseous mass containing elements such as nitrogen, oxygen, carbon, hydrogen, etc. Molecules like water ($H_2O$), carbon dioxide ($CO_2$), methane ($CH_4$), ammonia ($NH_3$), etc were formed by these elements. As the water was formed, the earth surface cooled slowly and the inorganic molecules interacted with one another in water to form simple organic molecules such as sugars, fatty acids, amino acids, etc. Thus, for these reactions energy was provided. It was provided by solar radiation, lightning, volcanic eruptions, etc.

An atmosphere was assembled by Miller and Urey that was similar to the early earth (this had molecules like ammonia, methane and hydrogen sulphide, but no oxygen) over water. It was maintained at a temperature just below $100^\circ$C and sparks were passed through the mixture of gases to simulate lightning. At the end of the week, 15$\%$ of the carbon (from methane) was converted to simple compounds of carbon including amino acids which make up protein molecules.

Miller and Urey experiment

10. Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

Ans: In sexual reproduction, two parents are involved. The genes are contributed by both the parents to the offspring. Half the number of chromosomes from the father and half from the mother is obtained. which means that one copy of a gene is inherited from the father and another copy from the mother. So, two individuals having different variations give rise to a new individual by the combination of their DNA. Therefore, sexual reproduction leads to variations. In asexual reproduction, when the copying of DNA is not accurate, variation occurs. However, Sexual reproduction allows more variations and the resultant DNA is also able to survive, thus making the variations viable.

Sexual reproduction plays an important role for the organism to adapt better to the environment. Variations help the species to survive In all these conditions, variation helps the species to survive. Environmental conditions such as disease, pests, and food availability can suddenly affect a place. In this situation, only those variants can survive who are resistant to it. Gradually, it will lead to the evolution of a better-adapted species. Thus, variation helps in the evolution of sexually reproducing organisms.

However, in case of a sudden change in the environment of asexually reproducing species can cause their extinction.

11. How is the equal genetic contribution of male and female parents ensured in the progeny?  

Ans: The somatic cell of the body of each human being contains 23 pairs of chromosomes. Out of the 23 pairs of chromosomes, 22 pairs are known as autosomes and the remaining one pair is called sex chromosomes which are represented as X and Y. Two X chromosomes are present in females and one X and one Y chromosome are present in males. In the process of gametogenesis (gamete formation), meiosis occurs and the gametes receive half the number of chromosomes. Therefore, the male gametes have 22 autosomes and either X or Y chromosomes. The female gamete, on the other hand, has 22 autosomes and X chromosomes.

In the process of sexual reproduction, male and female gametes fuse and the number of chromosomes is again restored in the zygote. Thus, 

(i) From Male - the progeny receives 22 autosomes and one X or Y chromosome from male parent and 

(ii) From Female - the progeny receives 22 autosomes and one X chromosome from the female parent.

12. Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

Ans: One of the basic mechanisms of evolution is ‘Natural selection’. It offers survival advantages that favour variation. The individuals that have survival advantage reproduce within the population and pass on the favourable variation to the progeny. The evolution that is occurring within the organisms is a result of this natural selection. However, there can be some other variations that occur accidentally and do not offer any survival advantage. The frequency of the genes can be changed in some populations if such variations occurred even if they are not important for survival. This accidental change in small populations is referred to as genetic drift. So it can be said that both types of variations can survive in a population.

Class 10 Science Chapter 8 Heredity and Evolution - Quick Overview of Topics

Class 10 Science Chapter 8 NCERT Solutions for Heredity and Evolution -Quick Overview of Detailed Structure of Topics and Subtopics Covered.

Class 10 NCERT Solutions Chapter 8 Heredity and Evolution - Important Topics

Class 10 NCERT solutions help the students to go through the Important Highlights easily. Here, find the important topics in Chapter 8 - Heredity and Evolution- to crack your exams.

Mendel’s Experiments and Laws of Inheritance:

Gregor Mendel's experiments with pea plants.

The principles of dominance, segregation, and independent assortment.

Monohybrid and dihybrid crosses.

Sex Determination:

The chromosomal theory of sex determination.

The difference between XX and XY chromosomes.

The concept of genetic and environmental sex determination in various organisms.

Evolution and Speciation:

Charles Darwin proposed the concept of evolution by natural selection.

The process of speciation and how new species arise.

Factors leading to speciation include genetic drift, mutation, and migration.

Acquired and Inherited Traits :

The distinction between acquired traits and inherited traits.

Examples of each type and their implications for evolution.

How inherited traits are passed from one generation to the next.

Evolutionary Relationships :

The evidence for evolution includes fossil records, homologous structures, and molecular biology.

The concept of common ancestry and the Tree of Life.

Understanding phylogenetic relationships among species.

Benefits of NCERT Solutions for Class 10 Science Chapter 8 Heredity and Evolution

The Vedantu’s Class 10 NCERT Solutions For Chemistry Heredity and Evolution class 10 exercise answers provided herein PDFs offer various benefits, including:

Detailed explanations and step-by-step solutions for all topics are in Chapter 8.

Solutions curated by experienced educators to ensure accuracy and clarity.

Covers important concepts like the evidence for evolution, including fossil records, homologous structures, and molecular biology.

Clear and concise explanations using precise chemical terminology.

In-depth analysis of key concepts and their applications in real-life scenarios.

Heredity and Evolution class 10 exercise provides a detailed explanation of The distinction between acquired traits and inherited traits, Examples of each type and their implications for evolution, and How inherited traits are passed from one generation to the next.

Solutions to a variety of problems to strengthen analytical and problem-solving abilities.

Step-by-step solutions for numerical problems and reaction mechanisms.

Important Study Materials for Class 10 Chemistry Chapter 8 Heredity and Evolution

Students can access extra study materials on Heredity and Evolution. These resources are available for download and offer additional support for your studies.

The NCERT Solutions for Class 10 Science Chapter 8 - Heredity and Evolution, provided by Vedantu, is a valuable tool for Class 10 students. It helps introduce Science concepts in an accessible manner. The provided solutions and explanations simplify complex ideas, making it easier for Class 10 Students to understand the material. By using Vedantu's resources, Students can develop a deeper understanding of NCERT concepts. These solutions are a helpful aid for grade 10 students, empowering them to excel in their studies and develop a genuine appreciation for Class 10 Science Chapter 8 - Heredity and Evolution.

FREE PDF Links for Other Chapter-wise NCERT Solutions Class 10 Science

Related Links for Class 10 Science

FAQs on NCERT Solutions for Class 10 Science Chapter 8 Heredity and Evolution

1. What is the meaning of Evolution in Chapter 9 of Class 10 Science syllabus?

Evolution refers to the series of gradual changes observed in primitive organisms. Through these changes, new species have come into existence. To understand Evolution in detail, you can download the PDF of NCERT solutions for Class 10 Science Chapter 9 from the Vedantu App.

2. What is the meaning of analogous organs?

Analogous organs, in a living being, refers to such organs of different species which have similar functions. These organs might not have the same anatomical features. But they function exactly in the same way in every organism. For example, the wings of a bird and an insect have the same functions, both are used for flight. So, even though they have been derived from separate ancestors, they function the same. Thus, they are considered as analogous organs.

3. What is the meaning of heredity in chapter Heredity and Evolution class 10 solutions?

Heredity is the transmission of traits or characters from a parent to the offspring. The study of heredity is called genetics. All of this is included in the Heredity Class 10 NCERT Solutions.

4. What are the topics covered in the Heredity and Evolution of NCERT Solutions for Class 10 Science?

Chapter 8 class 10 science is a very important chapter, especially from the perspective of the board exam. The topics covered in this chapter include:

Accumulation Of Variation During Reproduction

Inherited Traits

Mendel’s Contribution

Expression Of Traits

Sex Determination

Acquired And Inherited Traits

Evolutionary Relationships

5. Do the NCERT Solutions for Class 10 Science Chapter 9 help students score well in the board exams?

NCERT Class 10 Science Chapter 8 ‘Heredity and Evolution’ is a major chapter in the Science syllabus. Students are likely to get several questions from this particular chapter in the exams and can score really well if they are thorough with all the solutions. ch 8 Science class 10  provided by Vedantu will let you access the solutions for this chapter whenever you want to practice the answers or revise the topics and help you score well in your board exams. All the PDFs of NCERT Solutions are available at free of cost on the Vedantu website and on the Vedantu app.

6. From where can I download the NCERT Solutions for Class 10 Science Chapter 9?

If you want to download CBSE NCERT Solutions for Chapter 8 Science Class 10 question answer, you can follow these steps:

Visit the page NCERT Solutions for Class 10 Science and select Chapter 8.

After this, you will get to the page that will have all the solutions for Chapter 8 in PDF format. 

You can also download the solutions. Click on the Download PDF option.

You will be redirected to a new page.

Click on download. With this, you can use the PDF offline.

7. Is the ‘Heredity and Evolution’ chapter important?

Class 10 Science Chapter 8 “Heredity and Evolution” is very important since it forms the basis for a student in biology. This chapter is very important since students can expect several questions from it, in their board examinations. Hence, if you study this chapter well, it will automatically increase your chances of scoring good marks in the Class 10 board exams. Refer to the Heredity class 10 questions and answers while preparing.

8. What are fossils Chapter 9?

Fossils are proof of our evolution. By definition, fossils refer to the dead and decaying remnants of living organisms that date centuries back in time. The remains are understood to solidify over time and form layers. “Fossils” is a major topic to be read from Chapter 8 since students are expected to get questions from this topic in their board examination as well, which is why it is essential to be well versed in it. Students can also refer to Heredity class 10 questions and answers for better understanding.

NCERT Solutions for Class 10 Science

Ncert solutions for class 10.

Class 10 Science Chapter 8 Case Based Questions - Heredity and Evolution

Case Study - 1

Change in non-reproductive tissues cannot be passed on to the DNA of the germ cells. Therefore the experiences of an individual during its lifetime cannot be passed on to its progeny, and cannot direct evolution. Consider another example of how an individual cannot pass on to its progeny the experiences of its lifetime. If we breed a group of mice, all their progeny will have tails, as expected. Now, if the tails of these mice are removed by surgery in each generation, do these tailless mice have tailless progeny? The answer is no, and it makes sense because removal of the tail cannot change the genes of the germ cells of the mice.

Q1: What are acquired traits? Explain with example. Ans: The traits which are gain while experiencing the life time, its not related to genetic material. Example:  If a person get injured during his life time and get handicapped. This trait will not pass to his progeny as it had acquired throughout his life. Q2: Who wrote origin of life on earth? Ans: Charles Darwin Q3: What do you meant by term speciation? Ans:  It is an evolutionary process in which new species are formed by developing distinct features from their species or by modifying their genetic material. Q4: What are the factors that gave rise to the formation of new species? Ans:  Geographical isolation, genetic drift, mutation and natural selection. Q5: What is natural selection? Ans: The process which occurs in nature by which organism adapt the changing environment and tend to survive in it and reproduce in it.

Case Study - 2

The two sexes participating in sexual reproduction must be somewhat different from each other for a number of reasons. How is the sex of a newborn individual determined? Different species use very different strategies for this. Some rely entirely on environmental cues. Thus, in some animals like a few reptiles, the temperature at which fertilised eggs are kept determines whether the animals developing in the eggs will be male or female. In other animals, such as snails, individuals can change sex, indicating that sex is not genetically determined. However, in human beings, the sex of the individual is largely genetically determined. In other words, the genes inherited from our parents decide whether we will be boys or girls.

Q1: How many chromosomes are there in human beings? Ans:  23 pairs in which 22 pairs are autosomal and one pair i.e 23rd pair is sex chromosome. Q2: What are the pair of sex chromosome present in both male and female? Ans: People have same set of chromosome i.e XX but male have different sets of chromosome i.e XY. Q3: How is the sex of the child determined in human beings? Ans:  The sex is determined by paternal chromosome i.e. XY if X alleles fused with X chromosome of female then it is a baby girl. If Y allele fuse with X chromosome of female during fertilisation then it will be a baby boy. Q4: What is hermaphrodites? Ans:  Those organisms who don't have separate sex organs i.e. both the sex organs are present in the same body. Example: Earthworm

Case Study - 3

The rules for inheritance of such traits in human beings are related to the fact that both the father and the mother contribute practically equal amounts of genetic material to the child. This means that each trait can be influenced by both paternal and maternal DNA. Thus, for each trait there will be two versions in each child. What will, then, the trait seen in the child be?

Q1: What were the contrasting traits used by mendel? Ans:  Tall and dwarf plant, round/ wrinkled seeds, white / violets flower and on the basis of pod colour etc. Q2: What was the phenotypic ratio of monohybrid cross? Ans:  3 : 1 here, 3 is for tall plants and 1 is dwarf plants. Q3: What was the genotypic ratio of monohybrid cross? Ans:  1 : 2 : 1 Q4: How does the traits get expressed? Ans: Genes control traits, the diploid organism inherit two alleles from a gene i.e one is from father and one is from mother.

Case Study - 4

The evolutionary relationships of the species we see around us. It is a sort of going backwards in time. We can do this by identifying hierarchies of characteristics between species. Similarities among organisms will allow us to group them and then study the groups. For this, which characteristics decide more fundamental differences among organisms, and which ones decide less basic differences? What is meant by ‘characteristics’, anyway? Characteristics are details of appearance or behaviour; in other words, a particular form or a particular function. That we have four limbs is thus a characteristic.

Q1: What is homologous organs? Ans: The organs which have similar structure but different functions. Example: limbs of human, bird, frog and lizard Q2: What are fossil? Ans: The preserved remains or traces of remains body parts of an organism is called fossil. Q3: What are analogous organ? Ans: Different structure but  same function. Example:  wings of bats and birds. Q4: How do we know how old the fossils are? Ans:  By using carbon dating , in these we used radioactive decay of carbon 14 isotopes. Q5: What does it infer ” if more characteristics of two species are common”? Ans: It means they are closely related and may one had evolved from other or both have common ancestors.

Case Study - 5

It is all very well to say that very dissimilar looking structures evolve from a common ancestral design. It is true that analysis of the organ structure in fossils allows us to make estimates of how far back evolutionary relationships go. Are there any current examples of such a process? The wild cabbage plant is a good example. Humans have, over more than two thousand years, cultivated wild cabbage as a food plant, and generated different vegetables from it by selection. This is, of course, artificial selection rather than natural selection.

Q1: What was the evolution history of cabbage? Ans: Earlier, the human beings cultivates the wild cabbage for food and had produced different varieties of cabbage by doing artificial selection. The different varieties were kohlrabi, cauliflower, broccoli, cabbage, red cabbage and kale. Q2: What is molecular phylogeny? Ans: It is a method to gather information of an organism regarding their evolutionary relationship. Q3: What are the different methods for tracing the evolutionary relationship? Ans:  Looking into the data of homologous organ and analogous organ, fossil and embryo development. Q4: Do you agree with the term that ” evolution should not be equated with progress”? Ans:  Yes, evolution leads to more and more complex body design over time. It doesnt mean that older design are inefficient. For example, the bacteria the most primitive and simplest type of organism live in any harsh habitat and still they are surviving. Q5: Give one examples of evolution by stages? Ans:  Earlier, birds have feather only for heating purpose but as time passes, they evolve and now the feathers are used for flight also.

Case Study – 6

Pure bred pea plant with smooth seeds (dominant characteristic) were crossed with pure bred pea plant with wrinkled seeds (recessive characteristic). The F1 generation was self pollinated to give rise to the F2 generation.

Q1: What is the expected observation of the F1 generation of plants? Ans:  All of them have smooth seeds. Q2: What is the expected observation of the F2 generation of plants? Ans: ¼ of them have wrinkled seeds and ¾ of them have smooth seeds Q3: What will be the genotypic ration of F2 offspring , also mention whether it will be homozygous or heterozygous ? Ans:  Genotypic ratio = 1 : 2 : 1

• Homozygous dominant
• Heterozygous dominant
• Homozygous recessive

Case Study - 7

A scientist cross pure-bred tall (dominant) pea plant with pure-bred dwarf (recessive) pea plant he will get pea plants of F1 generation. If now self-cross the pea plant of F2 generation is done, then we obtain pea plants of F2 generation.

Q1: State the type of plants not found in F2 generation but appeared in F2 generation, mentioning the reason for the same Ans: In the F1 generation, Dwarf trait is recessive trait which was not expressed. After self pollination, the recessive trait gets expressed in F2 generation Q2: State the ratio of tall plants to dwarf plants in F2 generation.. Write the full form of DNA. Ans:  Ratio – 3 : 1 Full form of DNA – Deoxyribonucleic acid Q3: What do the plants of F2 generation look like? Ans: All plants of F1 generation will be tall plants. Q4: How does the creation of variations in a species promote survival? Ans: Variations promote the survival only when the species wants to allow by itself for survive to the continuous changing environment and conditions. During variations, different species get different kinds of advantages depending on the nature.

Top Courses for Class 10

shortcuts and tricks

Mock tests for examination, viva questions, previous year questions with solutions, video lectures, sample paper, important questions, semester notes, practice quizzes, study material, past year papers, objective type questions, extra questions.

Case Based Questions: Heredity and Evolution Free PDF Download

Importance of case based questions: heredity and evolution, case based questions: heredity and evolution notes, case based questions: heredity and evolution class 10, study case based questions: heredity and evolution on the app.

Welcome Back

Create your account for free.

Forgot Password

Unattempted tests, change country, practice & revise.

• Class 6 Maths
• Class 6 Science
• Class 6 Social Science
• Class 6 English
• Class 7 Maths
• Class 7 Science
• Class 7 Social Science
• Class 7 English
• Class 8 Maths
• Class 8 Science
• Class 8 Social Science
• Class 8 English
• Class 9 Maths
• Class 9 Science
• Class 9 Social Science
• Class 9 English
• Class 10 Maths
• Class 10 Science
• Class 10 Social Science
• Class 10 English
• Class 11 Maths
• Class 11 Computer Science (Python)
• Class 11 English
• Class 12 Maths
• Class 12 English
• Class 12 Economics
• Class 12 Accountancy
• Class 12 Physics
• Class 12 Chemistry
• Class 12 Biology
• Class 12 Computer Science (Python)
• Class 12 Physical Education
• GST and Accounting Course
• Excel Course
• Tally Course
• Finance and CMA Data Course
• Payroll Course

Interesting

• Learn English
• Learn Excel
• Learn Tally
• Learn GST (Goods and Services Tax)
• Learn Accounting and Finance
• GST Tax Invoice Format
• Accounts Tax Practical
• Tally Ledger List
• GSTR 2A - JSON to Excel

Are you in school ? Do you love Teachoo?

We would love to talk to you! Please fill this form so that we can contact you

You are learning...

Chapter 9 Class 10 - Heredity and Evolution

Click on any of the links below to start learning from Teachoo ...

Teachoo is your one - stop solution for everything related to science as you can find all the concepts, NCERT questions along with extra questions that we call Teachoo questions as they are prepared by our experts.

Chapter 9 of Class 10, Heredity and Evolution, you are going to learn about how heredity and evolution works for humans.

You will start by learning about the reasons or causes behind the variations in human beings . Basically, why all humans possess traits that are different from each other.

Then you will understand the concept of heredity and how different traits are transferred from the parents to their offsprings . In this section, you will also learn about the contributions of the scientist Gregor Johann Mendel in the study of traits and heredity .

You will also learn about how the gender of a human offspring can be identified .

After that you will learn about how evolution works. In this section you are going to learn about Darwin's Theory given by the scientist Charles Robert Darwin .

You will also learn about the changes that have taken place in the bodies of humans as species from historical times .

NCERT Questions

Questions from inside the book, teachoo questions, mcqs from ncert exemplar, assertion reasoning questions (mcq), case based questions (including mcq), past year - 1 mark questions, past year - 2 mark questions, past year - 3 mark questions, past year - 5 mark questions.

What's in it?

Hi, it looks like you're using AdBlock :(

Please login to view more pages. it's free :), solve all your doubts with teachoo black.

NCERT Solutions for Class 6, 7, 8, 9, 10, 11 and 12

NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution

September 27, 2019 by Veerendra

NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution: In this article, we will provide you detailed NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution. These heredity and evolution class 10 exercise answers were prepared by the best faculty in India to score good marks in the subject Science.

Also working on NCERT Solutions For Class 10 Science Chapter 9 will give you a strong foundation on the competitive exams like JEE, NEET, UPSC, etc., Read on to find out everything about NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution .

Before getting into the details of  NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution, let’s have an overview of the list of topics and subtopics under class 10 biology heredity and evolution NCERT solutions:

• Heredity And Evolution

Accumulation Of Variation During Reproduction

• Inherited Traits
• Rules for the Inheritance of Traits – Mendel’s Contributions
• How do these traits get Expressed
• Sex Determination
• An Illustration
• Acquired and Inherited Traits
• Tracing Evolutionary Relationships
• Evolution by Stages

Human Evolution

Free download NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution PDF in Hindi Medium as well as in English Medium for CBSE, Uttarakhand, Bihar, MP Board, Gujarat Board, and UP Board students, who are using NCERT Books based on updated CBSE Syllabus for the session 2019-20.

• अनुवांशिकता एवं जैव विकास कक्षा 10 विज्ञान हिंदी में
• Class 10 Heredity and Evolution Important Questions
• Heredity and Evolution Class 10 Notes
• Heredity and Evolution NCERT Exemplar Solutions
• Heredity and Evolution Class 10 Extra Questions
• Class 10 Heredity and Evolution Mind Map

NCERT Solutions for Class 10 Science Chapter 9 Intext Questions

Page Number: 143

Question 1. If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier ? Answer: Trait B, because it is present in more members of the population. It is likely to have arisen earlier and has now spread to 60% of the population. Trait A is new and has spread to only 10% of the population.

Question 2. How does the creation of variations in a species promote survival ? Answer: The variations provide stability to the population of various species by preventing them from getting wiped out during adverse conditions. The natural environment also changes, and variations in species which become suited to the environment help it to survive.

Page Number: 147

Question 1. How do Mendel’s experiments show that traits may be dominant or recessive ? [AICBSE 2015] Answer: Mendel took pea plants with contrasting characteristics tall plant and dwarf (or short) plant. On cross pollination, he got all tall plants in first generation (F 1 ). But by the self¬pollination of F 1 tall plants, the plants of second generation consisted of tall and short pants in the ratio of 3 : 1. On the basis of these experiments, the characteristics appeared in first generation were called dominant (i.e. tall plants) and the characteristics that did not appear were called recessive (dwarf i.e. plants).

Question 2. How do Mendel’s experiments show that traits are inherited independently ? [AICBSE 2015] Answer: Mendel took two pairs of alternate expression of two traits and carried out dihybrid crosses by crossing them. The traits appeared in first generation were termed as dominant. When he used these F 1 progeny to generate F 2 progeny by self-pollination plants of different types were produced. In some plants both the traits were dominant, while in some plants both were recessive and some plants exhibited mixed traits. This indicates that traits are inherited independently.

Question 3. A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant ? Why or why not ? Answer: This information is not enough. This is because each individual is carrying two alleles. The recessive trait can occur only when who alleles are similar. It blood group A is dominant and O is recessive, then daughter can have blood group O only when both recessive alleles occur together in mother, and father has one allele of O and other of A.

Question 4. How is the sex of the child determined in human beings ? OR “The sex of a newborn child is a matter of chance and none of the parents may be considered responsible for it.” Justify this statement with the help of a flow chart showing determination of sex of a newborn. [CBSE (Delhi) 2013] Answer: Half of the male gametes (sperms) carry X chromosome and other half carry Y chromosomes. All the female gametes carry only X chromosomes. When a sperm fertilizes an egg, the following situations become possible.

• (i) When a sperm carrying X chromosome fertilises an egg that contains only X chromosome), the resulting zygote develops into a female (XX condition).
• (ii) When a sperm carrying Y chromosome fertilises an egg (that contains only X chromosome), the resulting zygote develops into a male (XY condition).

Page Number: 150

Question 1. What are the different ways in which individuals with a particular trait may increase in a population ? Answer: Different ways in which individuals with a particular trait may increase in a population are as follow :

• If it gives the benefit of survival through natural selection.
• Due to a sudden increase in a particular trait in a population, i.e., by genetic drift.

Question 2. Why are traits acquired during the life-time of an individual not inherited ? Answer: The traits acquired during the life-time are changes in the non-reproductive cells of the organisms and are not capable of being passed on to the next generation.

Question 3. Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics ? Answer: The small numbers of surviving tigers are a cause of worry from the point of view of genetics because in tigers there are negligible genetic variations. Due to this they are not well adapted. The rapid environmental changes cannot be favouable for them. If these changes are not controlled, tigers would be wiped out.

Page Number: 151

Question 1. What factors would lead to the rise of a new species ? Answer: The factors that would lead to the rise of a new species are the following :

• Geographical isolation of a population caused by various types of barriers (such as mountain ranges, rivers and sea). The geographical isolation leads to reproductive isolation due to which there is no flow of genes between separated groups of pupulation.
• Genetic drift caused by drastic changes in the frequencies of particular genes by chance alone.
• Variations caused in individuals due to a natural selection.

Question 2. Will geographical isolation be a major factor in the speciation of a self- pollinating plant species ? Why or why not ? Answer: The geographical isolation cannot be major factor in the speciation of a self-pollinating plant species because it does not have to look the plants for its process of reproduction to be carried out.

Question 3. Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually ? Why or why not ? Answer: Geographical isolation cannot be a major factor in the speciation of an asexually reproducing organism because it does not require any other organism to carry out reproduction.

Page Number: 156

Question 1. Give an example of characteristics being used to determine how close two species are in evolutionary terms. Answer: If similar characteristics are shown in different organisms, then these are considered to be inherited from the common ancestry. It also shows the closeness of the species. For example, bats and birds have some similarity in their wings, so they are closely related, while lizard and squirrel do not have wings so these are not closely related to the birds and bats.

Question 2. Can the wing of a butterfly and the wing of a bat be considered homologous organs ? Why or why not ? Answer: The wings of a butterfly and the wings of a bat cannot be considered to be homologous organs because they have different basic designs though they are used for the same purpose of flying. They are analogous organs.

Question 3. What are fossils ? What do they tell us about the process of evolution ? Answer: Fossils : Fossils are the remains or traces of a dead organism. These are formed through the formation of sedimentary rocks. They provide following information on the process of evolution.

• They tell about the changes that occured on the earth’s surface and the corresponding organisms.
• They tell about the gradual development of complex structured organisms from simple structured organisms.
• It is known through them that birds are evolved from reptiles.
• They state that angiosperms are developed from pteriodophytes and gymnosperms.
• They exhibit the process of humana evolution.

Page Number: 158

Question 1. Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species ? Answer: This is because although genetic make up of humans may be slightly different in different races of people, there is no reproductive isolation. Reproductive isolation differentiates one species from the other. Human beings different in size, colour and looks can marry among themselves and produce fertile offspring.

Question 2. In evolutionary terms, can we say which among bacteria, spiders, fish and chimpanzees have a ‘better’ body design ? Why or why not ? Answer: Bacteria is a primitive organism as they came into being very early in evolution. But these organisms are still surviving in the present conditions after millions of years. This is because they have adapted well to the changing environment over these years. Same is the case for all other organisms like spiders, fishes and chimpanzees which have adapted to their environment and have survived. Therefore, all the organisms which exist have a body design which is better as it is suited to their environment.

NCERT Solutions for Class 10 Science Chapter 9 Textbook Chapter End Questions

Question 1. A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as: (a) TTWW (b) TTww (c) TtWW (d) TtWw Answer: (c) TtWW

Question 2. An example of homologous organs is : (a) our arm and a dog’s fore-leg (b) our teeth and an elephant’s tusks (c) potato and runners of grass (d) all of the above Answer: (d) All of the above

Question 3. In evolutionary terms, we have more in common with : (a) a Chinese school-boy (b) a chimpanzee (c) a spider (d) a bacterium Answer: (a) A Chinese school-boy

Question 4. A study found that children with light coloured eyes are likely to have parents with light coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive ? Why or why not ? Answer: This information is not complete. On the basis of this, it cannot be decided light colour trait is dominant or recessive. So it cannot be said until one does not know the nature of this trait in the parents.

Question 5. How are the areas of study-evolution and classification interlinked ? OR ‘Two areas of study namely ‘evolution’ and ‘classification’ are interlinked”. Justify this statement. [AICBSE 2016] Answer: Classification of organisms is based on relative similarities and differences among organisms. Resemblances in organisms are because they have arisen from a common ancestor and differences in them are due to adaptations to different types of environment. Since the organisms can be graded in order of increasing complexity it indicates at the concept of evolution.

Question 6. Explain the terms analogous and homologous organs with examples. [CBSE 2011,2013, 2014] Answer: Analogous organs : Those organs which have different basic structure (or different basic design) but have similar appearance and perform similar functions are called analogous organs. For example, The wings of an insect and a bird are analogous organs.

Homologous organs :  Those organs which have the same basic structure (or same basic design) but different functions are called homologous organs. For example, The wing of a bat, flipper of a seal, front leg of a horse and arm of a man are homologous organs.

Question 7. Outline a project which aims to find the dominant coat colour in dogs. Answer: Suppose a black homozygous male is mated with a white homozygous female. If the progeny has all black dogs then the dominant coat colour is black.

Question 8. Explain the importance of fossils in deciding evolutionary relationships. Answer: Fossils play important role in providing evolutionary evidences because by knowning the age of fossils we can know about the evolution process of an organism. For example, a fossil bird called archaeopteryx that looked like a bird had many other features of reptiles. It had feathered wings like those of birds, but teeth and tail like those of reptiles. Archaeopteryx is, therefore, a connecting link between the reptiles and birds, and hence suggests that the birds have evolved from the reptiles.

Question 10. Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually ? [CBSE 2011,2014] Answer: During sexual reproduction there is ‘crossing over’ of chromosomes, that gives rise to variations. These variations are inherited and increase the chances of survival of an organism.

• In sexual reproduction variations may occur due to errors in DNA copying.
• There may be variations due to interchange of homologous chromosomes during crossing over of male and female.
• In sexual reproduction, it is not predetermined that which gamete would fuse with another gamete. It depends only on chance. It is also a reason of variation. These variations enable the organisms to adapt themselves to the changing conditions and also help to give rise to new species.

Question 11. How is the equal genetic contribution of male and female parents ensured in the progeny ? [CBSE 2011, 2013] Answer: Genetic material in most organisms is present in pairs of chromosomes. Gametes in the sexually reproducing organisms are formed by the process of meiosis during which half of the genetic material goes into each gamete. When the gametes from male and female parents fuse with each other during sexual reproduction, the normal complement is restored. Half of the genetic material comes from the female and half from the male.

Question 12. Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement ? Why or why not? Answer: Yes, variations that confer an advantage to an individual organism are inherited. The organism can survive longer in an environment and maintain its existence in the population.

Heredity and Evolution: Heredity; Mendel’s contribution- Laws for inheritance of traits, Sex determination : brief introduction; Basic concepts of evolution.

Formulae Handbook for Class 10 Maths and Science

Question 1. If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% Of the same population, which trait is likely to have arisen earlier ? Answer: As species are asexually reproducing, there would be only very minor differences generated due to small inaccuracies in DNA copying, so trait B, which exists in 60% of the same population may get inherited earlier while trait A, which exists in 10% of the population may be originated late due to variations. Thus, trait B have arisen earlier since it is present in 60% of the same population.

Question 2. How does the creation of variations in a species promote survival ? Answer: Natural selection selects the individuals having useful variations which ensure their survival in the prevailing conditions of environment. Variant individuals that can withstand or cope with prevailing environment will survive better and will increase in number through differential reproduction.

More Resources for CBSE Class 10

NCERT Solutions

• NCERT Solutions for Class 10 Science
• NCERT Solutions for Class 10 Maths
• NCERT Solutions for Class 10 Social
• NCERT Solutions for Class 10 English
• NCERT Solutions for Class 10 Hindi
• NCERT Solutions for Class 10 Sanskrit
• NCERT Solutions for Class 10 Foundation of IT
• RD Sharma Class 10 Solutions

Question 1. How do Mendel’s experiments show that traits may be dominant or recessive ? Answer: Mendel took pea plants with contrasting characteristics – tall plant and dwarf (short) plant. On cross pollination, he got all tall plants in F1 generation. Then by self pollination of F1 tall plants, he produced second generation (F2) consisting of tall and short plants in the ratio of 3 : 1. Then he concluded that, ‘T’ (tall) trait is dominant while ‘t’ trait for shortness is recessive.

Download NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution PDF

Question 2. How do Mendel’s experiments show that traits are inherited independently ? Answer: In a dihybrid cross made by Mendel, it was observed that when two pairs of traits or characters were considered; each trait expressed independent of the other. Thus, Mendel was able to propose the Law of Independent Assortment which says about independent inheritance of traits.

Question 3. A man with blood group A marries a woman with blood O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O is dominant ? Why or why not ?

Answer: No. This information is not sufficient to determine which of the traits − blood group A or O − is dominant. This is because we do not know about the blood group of all the progeny.Blood group A can be genotypically AA or AO. Hence, the information is incomplete to draw any such conclusion.

Question 1. What are the different ways in which individuals with a particular trait may increase in a population ? Answer: Different ways are : variation, natural selection and genetic drift (isolation).

Question 2. Why are traits acquired during the lifetime of an individual not inherited ? Answer: Because acquired characters bring changes only in non-reproductive tissues and cannot change the genes of the germ cells. Thus, acquired traits cannot be passed to next generation.

Question 3. Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics ? Answer: (i) If any natural calamity occurs and kills these small number of surviving tigers, they can become extinct resulting in the loss of some genes forever. (ii) Small number will lead to little recombination and, therefore, lesser variations. These both are very important for giving better survival chances to the species. (iii) Less number of species means lesser extent of diversity and lesser number Of traits which reduces the chances of adaptability with respect to the change in the environment.

Question 1. What factors could lead to the rise of a new species ? Answer: Genetic variations, natural selection and reproductive isolation could lead to the rise of a new species.

Question 2. Will geographical isolation be a major factor in the speciation of a self-pollinating plant species ? Why or why not ? Answer: No, because pollination occurs on the same plant in self-pollinating plant species.

Question 3. Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually ? Why or why not ? Answer: No, because asexual reproduction involves single parent or organism.

Question 1. Give an example of characteristics being used to determine how close two species am in evolutionary terms ? Answer: Homologous organs, analogous organs and vestigial organs help to identify evolutionary relationships amongst the species.

Question 2. Can the wing of butterfly and the wing of a bat be considered homologous organs ? Why or why not ? Answer: No, wing of a bat and wing of a bird cannot be considered as homologous organs because they have different basic structure.

Question 3. What are fossils ? What do they tell us about the process of evolution ? Answer: Fossils are the impression or remains of ancient life found preserved in the sedimentary rocks. Fossils are direct evidences of evolution. Fossils also help to identify evolutionary relationship between apparently different species. They also tell about the extent of evolution that has taken place.

Page 158 Question 1. Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species ? Answer: They look different because of interaction of genes with environment which results in change in their appearance. But they belong to the same species as they have same number of chromosomes and can breed among themselves.

Question 2. In evolutionary terms, can we say which among bacteria, spiders, fish and chimpanzees have a ‘better body design’ why or why not ? Answer: No, because different designs are the product of evolution and different species have different body design to suit or adapt to their environment.

Question 1. A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing whfte flowers. The progeny all bore violet flowers, but almost half of them are short. This suggests that the genetic make-up of the tall parent can be depicted as (a) TTWW (b) TTww (c) TtWW (d) TtWw Answer: (c) Genetic make-up of tall plant can be depicted by TtWW.

Question 2. An example of homologous organs is (a) our arm and a dogs fore-leg. (b) our teeth and an elephants tusks. (c) potato and runners of grass. (d) All of the above. Answer: (d) Both organs in all options have same basic structural design but have different functions and appearance.

Question 3. In evolutionary terms, we have more in common with (a) a Chinese school-boy. (b) a chimpanzee. (c) a spider. (d) a bacterium. Answer: (a) A Chinese school-bpy is also a human being.

Question 4. A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not? Answer: We can say that light eye colour trait is dominant because only dominant traits are expressed in the first generation.

Question 5. How are the areas of study – evolution and classification— inteilinked? Answer: Evolution and classification are interlinked with each other in many ways. Classification is the most important term to explain evolution. It is based on the similarities and differences between two species or among two organisms. More closer the characteristics, the moe doser is the evolution and chances to be in the same group of classification. Thus, the classification of species is a reflection of their evolutionary relationship.

Question 6. Explain the terms analogous and homologous organs with examples. Answer: Analogous organs are those organs which have different basic structural designs and developmental origins but have similar appearance and perform similar functions. Examples: Wings of an insect and wings of a bat. Homologous organs are those organs which have the same basic structural design and developmenta’ origin but have different functions and appearance. Examples: Forelimbs of frog and forelimbs of human.

Question 8. Explain the importance of fossils in deciding evolutionary relationships. Answer: Fossils and their study is useful to know about the species which are no longer alive. They provide evidence and missing links between two classes. They are helpful in forming a sequence of organisms in the pathway of evolution. Thus, fossils have importance in deciding evolutionary relationships.

Question 9. What evidence do we have for the origin of life from inanimate matter? Answer: Stanley L. Miller and Harold C. Urey provided evidence regarding origin of life from inanimate matter. They assembled an atmosphere similar to that existed on early earth. The atmosphere had molecules like ammonia, methane, hydrogen sulphide and water, but no oxygen. The mixture was maintained at a temperature just below 100◦C and sparks were passed through the mixture of gases. At the end of a week, 15% carbon from methane had been converted to simple compounds of carbon like aminoacids which make up protein molecules. So, life arose afresh on earth.

Question 10. Explain how sexual reproduction gives rise to more viable variations that asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually ? Answer: Variations occurring during sexual reproduction may be due to:

• Separation of homologous chromosomes (by chance only) during gamete formation.
• Crossing over (recombination) of homologous chromosomes.
• Fertilisation of gametes to form zygote.
• Errors during DNA copying or mutations.

In asexually reproducing organisms only errors during DNA copying or mutations cause variations. Since the extent of variations is much larger in sexually reproducing organisms, therefore, the chances of evolution is also much in sexually reproducing These variations enable the organisms to adapt themselves to the changing conditions and also help to face the struggle for Over the time, they and rise to new species.

Question 11. How is the equal genetic contribution of male and female parents ensured in the progeny? Answer: Genetically organisms are of types

(i) Haploid : They have single set of chromosomes, where each chromosome is represented singly. As the chromosomes are the bearer of genes so haploids have single set of genes. A single gene determines the expression of character. (ii) Diploid : ‘They have two sets Of homologous chromosomes, where the chromosome occur in pair, one maternal contributed by the mother through her ovum and the second Of the pair is contributed by the male parent through his sperm. The resultant cell zygote produces by the fusion of male and female gametes have two sets of chromosomes –  each set contributed’ by each parent. In diploids a character is controlled by two genes/factors. Both the father and mother contribute practically equal amount of genetic material to the child. It means that each trait can be influenced by both paternal and maternal DNA.

Question 12. Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement ? Why or why not ? Answer: No, many of the times the variations are not advantageous to an individual organism but still survive in a population, e.g., take the case of free ear lobe and attached ear lobe. Most of the other variations not only give survival advantage to an individual but also contribute to genetic drift. Thus, we can say that most of the variations lead to better adaptation of an organism to the changing environment. In this way, it gives survival advantage to that organism and will also survive in the coming population.

Multiple Choice Questions (MCQs) [1 Mark each]

Question 1. An example of homologous organs is [NCERT] (a) our arm and a dog’s foreleg (b) our teeth and an elephant’s tusks (c) potato and runners of grass (d) All of the above Answer: (a) Our arm and a dog’s foreleg is the example of homologous organs.

Question 2. The science, which deals with study of heredity and variations is called (a) phylogeny (b) embryology (c) genetics (d) palaeontology Answer: (c) The genetics is the study of heredity and variations and includes their occurrence, causes, benefits, disadvantages, significance, etc.

Question 3. Archaeopteryx is a connecting link between (a) reptiles and aquatic animals (b) birds and insects (c) reptiles and birds (d) birds and dinosaurs Answer: (c) Archaeopteryx is a connecting link- between the reptiles and birds. It appears like a bird, but has other features which are present in reptiles, e.g. it has wings like bird, but teeth and tail like the reptilians.

Question 4. For palaeontological studies a scientist will gather the evidences from (a) study of homology (b) study of analogy (c) fossils (d) All of these Answer: (d) Study of homologous and analogous organs indicates the origin and modification in organisms and study of fossils indicates the age and features of an organism.

Question 5. In evolutionary terms, we have more in common with [NCERT] (a) a Chinese school boy (b) a chimpanzee (c) a spider (d) a bacterium Answer: (a) Chinese school boy because both of us belong to the same species, i.e. Homo sapiens.

Question 6. Aditya was observing some organisms in lab and tried to compare them. The presence of which organs will confirm to him that they share evolutionary history? (a) Analogous organs (b) Paralogous organs (c) Homologous organs (d) None of these Answer: (c) Homologous organs are present in organisms who share evolutionary history. However, these organs perform different functions in different organisms.

Question 7. New species may be formed if I. DNA undergoes significant changes in germ cells. . II. chromosome number changes in the gamete. III. there is no change in the genetic material. IV. mating does not take place. (a) I and II (b) I and III (c) II, III and IV (d) I, II and III Answer: (a) New species may be formed if the DNA changes are severe enough, such as a change in the number of chromosome. This leads to new variations.

Question 8. Which of the following statements is not true with respect to variation? (a) All variations in a species have equal chance of survival. (b) Change in genetic composition results in variation. (c) Selection of variants by environmental factors forms the basis of evolutionary processes. (d) Variation is minimum in asexual reproduction. Answer: (a) All variations in a species do not have equal chances of survival. Some of the variations may be so drastic that the new DNA copy cannot work with the cellular apparatus it inherits. Such, a newborn cell dies soon.

Question 9. Select the statement that describes characteristics of genes. . (a) Genes are specific sequence of bases in a DNA molecule. (b) A gene does not code for proteins. (c) In individuals of a given species, a specific gene is located on a particular chromosome. (d) Each chromosome has only one gene. Answer: (b) Genes are stretches of DNA found on chromosomes of a cell. A gene contains information for making proteins in a cell. A specific gene is located on a particular chromosome in individuals of a given species.

Question 10. If a round, green seeded pea plant (RRyy) is crossed with wrinkled, yellow seeded pea plant (rrYY), the seeds produced in F1 – generation will be [NCERT Exemplar] (a) round and yellow (b) round and green (c) wrinkled and green (d) wrinkled and yellow Answer: (a) The cross between RRyy and rrYY seeds will produce RrYy (round and yellow) seeds in F1-generation, because round and yellow are the dominant traits.

Question 11. From the list given below, select the character, which can be acquired but not inherited. [NCERT Exemplar] (a) colour of eye (b) colour of skin (c) size of body (d) nature of hair Answer: (c) Acquired traits develop in response to the environment. The size of the body is an acquired trait because it can vary based on the availability of less or more food. The other three colour of eye and skin and nature of hair are characters inherited from the parents.

Question 12. According to the evolutionary theory, formation of a new species is generally due to [NCERT Exemplar] (a) sudden creation by nature. (b) accumulation of variations over several generations. (c) clones formed during asexual reproduction. (d) movement of individuals from one habitat to another Answer: (b) Accumulation of variations over several generations forms new species. Genetic drift accumulates different changes in sub-populations of a species. Also, natural selection may also operate differendy in the different geographic locations. Eventually, different groups of new species will be formed.

Question 13. Select the incorrect statement. [NCERT Exemplar] (a) Frequency of certain genes in a population changes over several generations resulting in evolution. (b) Reduction in weight of the organism due to starvation is genetically controlled. (c) Low weight parents can have heavy weight progeny. (d) Traits which are not inherited over generations do not cause evolution. Answer: (b) The weight reduction due to starvation will not change the DNA of the germ cells, because low weight is not a trait that is genetically controlled or inherited. Also, low weight parents may have heavy weight progeny.

Question 14. In human males all the chromosomes are paired perfectly except one. This/these unpaired chromosome is/are I. large chromosome II. small chromosome III. Y-chromosome IV X-chromosome (a) I and II (b) Only III (c) III and IV (d) II and IV Answer: (c) In human males, one pair called the sex chromosomes are unpaired. Here, one is a normal-sized X-chromosome while other is a short Y-chromosome. Women have a perfect pair of sex chromosomes, both called X.

Question 15. Rajneesh was studying the fossils of two different types, fossil A was found in upper layer of Earth and B in deeper layers. What can be predicted regarding the age of these fossils? (a) A has recently become extinct (b) B has become extinct recently (c) The time of extinction cannot be determined (d) None of the above Answer: (a) Since, fossil A was found in upper layer of earth, it suggests that the organism has become extinct recently. Fossil B found in deeper layer must have become extinct long time ago and deposition of other layers occurred over it during this period.

NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution (Hindi Medium)

Class 10 Science Heredity and Evolution Mind Map

• Characters or features or traits are inherited from one generation to the next during reproduction.
• This inheritance provides both a common basic body design & subtle changes in it for next generation.
• When this generation reproduces, the offspring would have differences they inherit from previous generation as well as newly created differences.
• Accumulation of these differences generation after generation leads to the development of variations in a population.
• Different variations provide different advantages to the population and the variation which provide best survival advantages are inherited to the next generation.
• For e.g. bacteria having variation to tolerate heat will survive and multiply better in heat wave.

Heredity Heredity refers to the transmission of characteristics from parent to offspring by means of genes in the chromosomes. Mendel’s Contributions

• Mendel was the first scientist whose studies lead to the formulation of laws of inheritance.
• He conducted cross hybridization experiments of garden pea plant (Pisum sativum) and studied the transmission of characters that had two contrasting traits such as round/wrinkled seeds, tall/short plants, white/’violet flowers etc.

Experiment 1:  He cross pollinate pure breeds of tall (TT) & dwarf (tt) pea plant and calculated the percentages of tall & dwarf progeny. Observation:  F 1  generation was tall (Tt) with no halfway characteristics. F 2  generation produced by self pollination of F 1  included tall and short plants in 3:1. (Genotypic ratio 1:2:1 for TT:Tt:tt) Inference:  This indicates that both the tallness & shortness traits were inherited in the F, plants, but only the tallness trait was expressed. Thus, two copies of the trait are inherited in each sexually reproducing organism. These two may be identical (TT or tt) or may be different (Tt), depending on the parentage. Conclusion:  This study leaded to the formulation of two laws: Law of dominance:  states that only one character expresses itself in F, generation. Law of segregation:  states that the two alleles of a character in an individual get separated or segregated during gamete formation and distributed randomly in gametes.

Experiment 2: He crossed the plant with two different characteristics such as tall plant with round seed and short plant with wrinkled seed. Other example may include round & green seeds (RRyy) and wrinkled & yellow seeds (rrYY). Observation: F 1 generation; all were tall & round i.e. tall & round are dominant. F 2 generation; tall plants with round seeds, tall with wrinkled seeds, short with round seeds, and short plants with wrinkled seeds in 9:3:3:1. Similarly, round & yellow, round & green, wrinkled & yellow, and wrinkled & green in 9:3:3:1. Inference: The tall/short trait and the round seed/wrinkled seed trait are independently inherited. Conclusion: It formulated the law of independent assortment which states that genes of different characters located in different pairs of chromosomes are independent of one another in their segregation during gamete formation.

Sex Determination Different species use different strategies for this:

• Environment: for e.g. the temperature at which fertilised eggs are kept determines the sex of developing animals in the eggs. It is observed in animals like crocodile, turtle etc.
• Snails can change sex. indicating that sex is not genetically determined.
• Humans have 22 autosomal & 1 sex chromosome pairs. Females have XX & males have XY. Hence, sex of a child is determined by what he/she has inherited (X or Y) from the father since, child will always inherit X from the mother. If X is inherited from father then child will be a girl & if Y is inherited then a child will be a boy.

• It refers to gradual change in the characteristics of the population (plants & animals) over successive generations.
• Errors in DNA copying during reproduction, mutations, & natural selection account for the evolution.
• Evolution gives rise to such a biodiversity at each level of biological organization such as at species level, among individuals, molecules etc.

Evolution And Classification Classification is the process by which organisms are grouped into convenient categories based on some easily observable characters.

Characters such as cell type (prokaryote or eukaryote), single cell or multi cellular, presence or absence of nucleus, autotrophic (such as photosynthesis) or heterotrophic, sexual or asexual reproduction etc. are used to classify different organisms in different groups.

The more characteristics two species will have in common, the more closely they are related. And the more closely they are related, the more recently they will have had a common ancestor. For e.g. brother & sister are more closely related than a girl & her first cousin. Therefore, classification of species gives a reflection of their evolutionary relationship.

Tracing Evolutionary Relationships Few evidences which help us to trace evolutionary relationships among different organisms or species:

• Homologous: Similar structure different functions. It indicates common ancestry for e.g. bones of forelimbs in frog, lizard, bird & human.
• Analogous: Similar functions but different structure. Different structures evolved for same function & hence having similarity. For e.g. wings of bats & birds, eye of octopus & mammals, etc.
• The age of the fossils can be estimated by two ways; relative depth of the fossils, dating fossils i.e. detection of ratios of different isotopes of the same element in the fossil material
• It refers to a gradual evolutionary process by which populations evolve to become different species.
• Reproductive and geographical isolation play an important role in the process of speciation. They result in change in the frequency of an existing gene variant in a population i.e. genetic drift.
• Over generations, genetic drift along with natural selection results in the formation of new’ species,
• Other factors that may result in speciation are sudden severe DNA changes (mutation) such as change in chromosomal no., variation such as female green beetle will not mate with red males. Her behavior ensures the reproductive isolation between them and thus results in generation of new’ species.

Evolution Should Not Be Equated With ‘progress’

• Evolution is simply the generation of diversity & shaping of diversity by environmental selection.
• The only progressive trend in evolution seems to be the emergence of more and more complex body designs over time. However, that doesn’t mean that the older designs are inefficient.
• For e.g. simplest life forms; bacteria inhabits the most inhospitable habitats like hot springs, deep-sea thermal vents & ice in Antarctica.
• Tolls, like excavating, time-dating and studying fossils, determining DNA sequences etc, have been used for studying human evolution.
• All humans are a single species regardless of skin color or human races.
• The earliest members of the human species, Homo sapiens, can be traced back to Africa i.e. we all come from Africa.
• A couple of hundred thousand years ago, some of our ancestors left Africa while others stayed on.
• The migrants slowly spread across the planet; from Africa to West Asia, then to Central Asia, Eurasia, South Asia, & East Asia.
• They travelled down the islands of Indonesia and the Philippines to Australia, and they crossed the Bering land bridge to the Americas.

We hope this detailed article on NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution is helpful. If you have any query regarding this article or  NCERT Solutions For Class 10 Science Chapter 9 Heredity and Evolution, leave your comments in the comment section below and we will get back to you as soon as possible.

NCERT Solutions for Class 10 Science All Chapters

• Chapter 1 Chemical Reactions and Equations
• Chapter 2 Acids, Bases and Salts
• Chapter 3 Metals and Non-metals
• Chapter 4 Carbon and Its Compounds
• Chapter 5 Periodic Classification of Elements
• Chapter 6 Life Processes
• Chapter 7 Control and Coordination
• Chapter 8 How do Organisms Reproduce?
• Chapter 9 Heredity and Evolution
• Chapter 10 Light Reflection and Refraction
• Chapter 11 Human Eye and Colourful World
• Chapter 12 Electricity
• Chapter 13 Magnetic Effects of Electric Current
• Chapter 14 Sources of Energy
• Chapter 15 Our Environment
• Chapter 16 Management of Natural Resources

Free Resources

Quick Resources

NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution

The Class 10 NCERT Solutions for Science Chapter 9 Heredity and Evolution includes all the intext and exercise questions. Class 10 Science Chapter 9 Heredity and Evolution NCERT questions and answers help students to clear their doubts and to obtain good marks in Class 10 board exam. All the solutions provided in this article are strictly based on the CBSE syllabus and curriculum.

Class 10 Science Chapter 9 NCERT Questions and Answers

Class 10 Science Chapter 9 Heredity and Evolution NCERT Questions and Answers are prepared by experts with a detailed explanation that will help students complete their assignments & homework. Having a good grasp over CBSE NCERT Solutions for Class 10 Science will further help the students in their preparation for board exams and other competitive exams such as NTSE, Olympiad, etc.

NCERT Solutions for Class 10 Science Chapter 9 Intext Questions

Intext Question (Page No. 143)

Question 1: If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Answer: In asexual reproduction, the reproducing cells produce a copy of their DNA through some chemical reactions. However, this copying of DNA is not accurate and therefore, the newly formed DNA has some variations.

It can be easily observed in the above figure that in asexual reproduction, very few variations are allowed. Therefore, if a trait is present in only 10% of the population, it is more likely that the trait has arisen recently. Hence, it can be concluded that trait B that exists in 60% of the same population has arisen earlier than trait A.

Question 2: How does the creation of variations in a species promote survival?

Answer: Sometimes for a species, the environmental conditions change so drastically that their survival becomes difficult. For example, if the temperature of water increases suddenly, most of the bacteria living in that water would die. Only few variants resistant to heat would be able to survive. If these variants were not there, then the entire species of bacteria would have been destroyed. Thus, these variants help in the survival of the species. However, not all variations are useful. Therefore, these are not necessarily beneficial for the individual organisms.

Intext Question (Page No. 147)

Question 1: How do Mendel’s experiments show that traits may be dominant or recessive?

Answer: Mendel selected true breeding tall (TT) and dwarf (tt) pea plants. Then, he crossed these two plants. The seeds formed after fertilization were grown and these plants that were formed represent the first filial or F1 generation. All the F1 plants obtained were tall.

Then, Mendel self-pollinated the F1 plants and observed that all plants obtained in the F2 generation were not tall. Instead, one-fourth of the F2 plants were short.

Self-pollination of F 1 plants

From this experiment, Mendel concluded that the F1 tall plants were not true breeding. They were carrying traits of both short height and tall height. They appeared tall only because the tall trait is dominant over the dwarf trait.

Question 2: How do Mendel’s experiments show that traits are inherited independently?

Answer: Mendel crossed pea plants having round green seeds (RRyy) with pea plants having wrinkled yellow seeds (rrYY).

Since the F1 plants are formed after crossing pea plants having green round seeds and pea plants having yellow wrinkled seeds, F1 generation will have both these characters in them. However, as we know that yellow seed colour and round seeds are dominant characters, therefore, the F1 plants will have yellow round seeds.

Then this F1 progeny was self-pollinated and the F2 progeny was found to have yellow round seeds, green round seeds, yellow wrinkled seeds, and green wrinkled seeds in the ratio of 9:3:3:1.

In the above cross, more than two factors are involved, and these are independently inherited.

Question 3: A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits − blood group A or O − is dominant? Why or why not?

Answer: Given information is not enough to tell us which characteristics are dominant –blood group A or O. Blood type A is always dominant in the type of ABO blood and blood type O is always recessive. Here, father’s group of blood may be genotypically AA (homozygous) or AO (heterozygous), where as that of mother can be OA or OO.

Question 4: How is the sex of the child determined in human beings?

Answer: In human beings, the females have two X chromosomes and the males have one X and one Y chromosome. Therefore, the females are XX and the males are XY.

The gametes, as we know, receive half of the chromosomes. The male gametes have 22 autosomes and either X or Y sex chromosome.

Type of male gametes: 22+X or 22+ Y.

However, since the females have XX sex chromosomes, their gametes can only have X sex chromosome.

Type of female gamete: 22+X

Thus, the mother provides only X chromosomes. The sex of the baby is determined by the type of male gamete (X or Y) that fuses with the X chromosome of the female.

Intext Question (Page No. 150)

Question 1: What are the different ways in which individuals with a particular trait may increase in a population?

Answer: An individual attribute could increase in a population within the following 2 ways:

(a) Natural selection:  if an attribute is useful to a population, it’ll increase naturally.

As an example – inexperienced colorize beetles is favorable because it helps them in camouflage against the predators.

(b) Genetic drift:  If a population faces an accident such majority of its members get killed, the remaining members can pass away their traits to the following generations. This may result in a rise of the attribute within the population.

Question 2: Why are traits acquired during the life-time of an individual not inherited?

Answer: This happens because an acquired trait involves change in non-reproductive tissues (somatic cells) which cannot be passed on to germ cells or the progeny. Therefore, these traits cannot be inherited.

Question 3: Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics?

Answer: The small numbers of surviving tigers are a cause of worry from the point of view of genetics because in tigers there are negligible genetic variations. Due to this they are not well adapted. The rapid environmental changes cannot be favouable for them. If these changes are not controlled, tigers would be wiped out.

Intext Question (Page No. 151)

Question 1: What factors could lead to the rise of a new species?

Answer: Factors that would cause the increase of a brand new species are as follows: (a) Natural activity. (b) Method of genetic drift. (c) Mutation. (d) Geographical isolation. (e) Environmental factors on the isolated populations. (f) Generative isolation for a protracted time. (g) Quantum of genetic variant transmissible from one generation to the following generation.

Question 2: Will geographical isolation be a major factor in the speciation of a self-pollinating plant species? Why or why not?

Answer: Geographical isolation can prevent the transfer of pollens among different plants. However, since the plants are self-pollinating, which means that the pollens are transferred from the anther of one flower to the stigma of the same flower or of another flower of the same plant, geographical isolation cannot prevent speciation in this case.

Question 3: Will geographical isolation be a major factor in the speciation of an organism that reproduces asexually? Why or why not?

Answer: Geographical isolation prevents gene flow between populations of a species whereas asexual reproduction generally involves only one individual. In an asexually reproducing organism, variations can occur only when the copying of DNA is not accurate. Therefore, geographical isolation cannot prevent the formation of new species in an asexually reproducing organism.

Intext Question (Page No. 156)

Question 1: Give an example of characteristics being used to determine how close two species are in evolutionary terms.

Answer: The presence of feathers in dinosaurs and birds indicates that they are evolutionarily related. Dinosaurs had feathers not for flying but instead these feathers provided insulation to these warm-blooded animals. However, the feathers in birds are used for flight. This proves that reptiles and birds are closely related and that the evolution of wings started in reptiles.

Question 2: Can the wing of a butterfly and the wing of a bat be considered homologous organs? Why or why not?

Answer: Homologous organs perform completely different functions and have different look however share common basic structural structure. The origin wings of a butterfly are composed of polysaccharide membrane, whereas wings of a bat are composed of bony skeleton. Hence, these aren’t homologous organs rather analogous organs.

Question 3: What are fossils? What do they tell us about the process of evolution?

Answer: Fossils: Fossils are the remains or traces of a dead organism. These are formed through the formation of sedimentary rocks. They provide following information on the process of evolution.

• They tell about the changes that occured on the earth’s surface and the corresponding organisms.
• They tell about the gradual development of complex structured organisms from simple structured organisms.
• It is known through them that birds are evolved from reptiles.
• They state that angiosperms are developed from pteriodophytes and gymnosperms.
• They exhibit the process of human evolution.

Intext Question (Page No. 158)

Question 1: Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species?

Answer: A species is a group of organisms that are capable of interbreeding to produce a fertile offspring. Skin colour, looks, and size are all variety of features present in human beings. These features are generally environmentally controlled. Various human races are formed based on these features. However, there is no biological basis to this concept of races.

Therefore, all human beings are a single species as humans of different colour, size, and looks are capable of reproduction and can produce a fertile offspring.

Question 2: In evolutionary terms, can we say which among bacteria, spiders, fish and chimpanzees have a ‘better’ body design? Why or why not?

Answer: No, we can’t say there’s a better body design as these organisms evolved to survive in the environment according to their needs. If a chimpanzee has strong limbs capable of multiple actions, the bacteria can survive in extreme conditions where it is impossible for other organisms. Therefore there is no better design of the body.

NCERT Solutions for Class 10 Science Chapter 9 Exercise Questions

Question 1: A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as

(a) TTWW (b) TTww (c) TtWW (d) TtWw

Answer: (c) TtWW

Since all the progeny bore violet flowers, it means that the tall plant having violet flowers has WW genotype for violet flower colour. Since the progeny is both tall and short, the parent plant was not a pure tall plant. Its genotype must be Tt.

Therefore, the cross involved in the given question is

 Therefore, half the progeny is tall, but all of them have violet flowers.

Question 2: An example of homologous organs is (a) our arm and a dog’s fore-leg (b) our teeth and an elephant’s tusks (c) potato and runners of grass (d) all of the above

Answer: (b) our teeth and an elephant’s tusks.

Question 3: In evolutionary terms, we have more in common with (a) a Chinese school-boy (b) a chimpanzee (c) a spider (d) a bacterium

Answer: (a) a Chinese school boy.

Question 4: A study found that children with light – coloured eyes are likely to have parents with light coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?

Answer: Let us assume that children with light – coloured eyes can either have LL or Ll or ll genotype. If the children have LL genotype, then their parents will also be of LL genotype.

If the children with light coloured eyes have ll genotype, then their parents will also have ll genotype.

Therefore, it cannot be concluded whether light eye colour is dominant or recessive.

Question 5: How are the areas of study − evolution and classification − interlinked?

Answer: Classification and evolution are extremely interlinked fields of study. Classification is influenced by evolution. The fashionable system of classification is additionally known as biological process classification; which implies it’s supported biological process relationships. Hence, evolution and classification are closely connected.

Question 6: Explain the terms analogous and homologous organs with examples.

Answer: Homologous organs: are similar in origin (or are embryologically similar) but perform different functions. For example, the forelimbs of humans and the wings of birds look different externally but their skeletal structure is similar. It means that their origin is similar (as wings in birds are modifications of forearm) but functions are different – the wings help in flight whereas human forearm helps in various activities.

Analogous organs : on the other hand, have different origin but perform similar functions. For example, the wings of a bird and a bat are similar in function but this similarity does not mean that these animals are more closely related. If we carefully look at these structures, then we will find that the wings of a bat are just the folds of skin that are stretched between its fingers whereas the wings of birds are present all along the arm. Therefore, these organs are analogous organs.

Question 7: Outline a project which aims to find the dominant coat colour in dogs.

Answer: Dogs have a variety of genes that govern coat colour. There are at least eleven identified gene series (A, B, C, D, E, F, G, M, P, S, T) that influence coat colour in dog.

A dog inherits one gene from each of its parents. The dominant gene gets expressed in the phenotype. For example, in the B series, a dog can be genetically black or brown. Let us assume that one parent is homozygous black (BB), while the other parent is homozygous brown (bb).

In this case, all the offsprings will be heterozygous (Bb).

Since black (B) is dominant, all the off-springs will be black. However, they will have both B and b alleles.

If such heterozygous pups are crossed, they will produce 25% homozygous black (BB), 50% heterozygous black (Bb), and 25% homozygous brown (bb) offsprings.

Question 8: Explain the importance of fossils in deciding evolutionary relationships.

Answer: Fossil give evidence about

(a) The organisms that lived way back like the fundamental quantity throughout that they lived, their structure etc.

(b) Biological process development of species i.e., line of their development.

(c) Connecting links between 2 teams. As an example, feathers gift in some dinosaurs implies that birds are terribly closely associated with reptiles.

(d) That organisms evolved earlier and which later.

(e) Development of complicated body styles from the straightforward body designs.

Question 9: What evidence do we have for the origin of life from inanimate matter?

Answer: A British scientist, J.B.S. Haldane, suggested that life originated from simple inorganic molecules. He believed that when the earth was formed, it was a hot gaseous mass containing elements such as nitrogen, oxygen, carbon, hydrogen, etc. These elements combined to form molecules like water (H 2 O), carbon dioxide (CO 2 ), methane (CH 4 ), ammonia (NH 3 ), etc.

After the formation of water, slowly the earth surface cooled and the inorganic molecules interacted with one another in water to form simple organic molecules such as sugars, fatty acids, amino acids, etc. The energy for these reactions was provided by solar radiations, lightning, volcanic eruptions, etc.

This was proved by the experiment of Stanley L. Miller and Harold C. Urey in 1953. They took a mixture of water (H 2 O), methane (CH 4 ), ammonia (NH 3 ), and hydrogen gas (H 2 ) in a chamber and sparks were passed through this mixture using two electrodes. After one week, 15% of the carbon from methane was converted into amino acids, sugars, etc. These organic molecules are polymerized and assembled to form protein molecules that gave rise to life on earth.

Question 10: Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

Answer: Sexual reproduction causes a lot of viable variations because of the subsequent reasons:

(a) Error in repetition of deoxy ribonucleic acid, that don’t seem to be extremely vital.

(b) Random segregation of paternal and maternal body at the time of sex cell formation.

(c) Exchange of genetic material between homologous chromosomes throughout formation of gametes.

(d) Accumulation of variations occurred because of reproduction over generation after generation and choice naturally created wide diversity.

(e) In case of agamogenesis, solely the terribly tiny changes because of inaccuracies in deoxy ribonucleic acid copying pass away the relative. Thus, off springs of agamogenesis are a lot of or less genetically just like their folks. So, it will be ended that evolution in sexually reproducing organisms proceed at a quicker pace than in asexually reproducing organisms.

Question 11: How is the equal genetic contribution of male and female parents ensured in the progeny?

Answer: In human beings, every somatic cell of the body contains 23 pairs of chromosomes. Out of these 23 pairs, the first 22 pairs are known as autosomes and the remaining one pair is known as sex chromosomes represented as X and Y.

Females have two X chromosomes and males have one X and one Y chromosome. The gamete receives half of the chromosomes. Therefore, the male gametes have 22 autosomes and either X or Y chromosome.

The female gamete, on the other hand, has 22 autosomes and X chromosome.

During reproduction, the male and female gametes fuse and thus the progeny receives 22 autosomes and one X or Y chromosome from male parent and 22 autosomes and one X chromosome from the female parent.

Question 12: Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

Answer: We agree with the statement that solely variations that confer a plus to a private organism can survive during a population. All the variations don’t have associate equal likelihood of extant within the setting within which they notice themselves. The possibilities of extant rely upon the character of variations. Totally different individual would have different reasonably benefits. Bacterium which will face up to heat will survive higher during a wave. Choice of variants by environmental factors forms the idea for revolutionary method.

Topics covered under Class 10 Science Chapter 9 Heredity and Evolution

Below we have listed the topics discussed in NCERT Solutions for Class 10 Science Chapter 9. The list gives you a quick look at the different topics and subtopics of this chapter.

NCERT Solutions for Class 10 Science Chapter 9 – A Brief Discussion

Chapter Overview: Have you ever wondered why you resemble some characteristics of your mother and father? The answer is pretty simple. It actually due to the inheritance of traits/characters that the offspring inherit from their parents. Inheritance of traits from parents is also called as heredity. In this chapter, you will learn how heredity brings variation in genes and helps in evolution. This chapter covers some important topics like how inherited traits get expressed in offsprings, speciation, evolution and classification. Heredity and Evolution is an interesting chapter. We advise you read the chapter in NCERT book for better understanding.

NCERT Solutions for Class 10 Science Chapter 9 Heredity and Evolution

Chapter 9 Heredity and Evolution Class 10 NCERT Solutions

Ncert solutions for class 10 science chapters:.

Why are acquired characters not inheritable?

What do you mean by chromosome, how can we trace evolutionary relationships, what is dna copying, what is the effect of dna copying which is not perfectly accurate on the reproduction process, contact form.

myCBSEguide

• Case Study Questions Class...

Case Study Questions Class 10 Science

Table of Contents

myCBSEguide App

Download the app to get CBSE Sample Papers 2023-24, NCERT Solutions (Revised), Most Important Questions, Previous Year Question Bank, Mock Tests, and Detailed Notes.

Download Case study questions for CBSE class 10 Science in PDF format from the myCBSEguide App . We have the new pattern case study-based questions for free download. Class 10 Science case study questions

This article will guide you through:

What are case study questions?

• Sample Papers with Case Study questions
• Class 10 Science Case Study question examples
• How to get case-based questions for free?
• How to attempt the case-based questions in Science?

Questions based on case studies are some real-life examples. The questions are asked based on a given paragraph i.e. Case Study.  Usually, 4-5 questions are asked on the basis of the given passage. In most cases, these are either MCQs or assertion & reason type questions. Let’s take an example to understand. There is one paragraph on how nitrogen is generated in the atmosphere. On the basis of this paragraph, the board asks a few objective-type questions. In other words, it is very similar to the unseen passages given in language papers. But the real cases may be different. So, read this article till the end to understand it thoroughly.

What is CBE?

CBSE stands for competency-based education. The case study questions are part of this CBE. The purpose of CBE is to demonstrate the learning outcomes and attain proficiency in particular competencies.

Questions on Real-life Situations

As discussed the case study questions are based on real-life situations. Especially for grade 10 science, it is very essential to have the practical knowledge to solve such questions. Here on the myCBSEguide app, we have given many such case study paragraphs that are directly related to real-life implications of the knowledge.

Sample Papers with Case Study Questions

Class 10 Science Sample Papers with case study questions are available in the myCBSEguide App . There are 4 such questions (Q.No.17 to 20) in the CBSE model question paper. If you analyze the format, you will find that the MCQs are very easy to answer. So, we suggest you, read the given paragraph carefully and then start answering the questions. In some cases, you will find that the question is not asked directly from the passage but is based on the concept that is discussed there. That’s why it is very much important to understand the background of the case study paragraph.

CBSE Case Study Sample Papers

You can download CBSE case study sample papers from the myCBSEguide App or Student Dashboard. Here is the direct link to access it.

Case Study Question Bank

As we mentioned that case study questions are coming in your exams for the last few years. You can get them in all previous year question papers issued by CBSE for class 1o Science. Here is the direct link to get them too.

Class 10 Science Case Study Question Examples

As you have already gone through the four questions provided in the CBSE model question paper , we are proving you with other examples of the case-based questions in the CBSE class 10 Science. If you wish to get similar questions, you can download the myCBSEguide App and access the Sample question papers with case study-type questions.

Case-based Question -1

Read the following and answer any four questions: Salt of a strong acid and strong base is neutral with a pH value of 7. NaCl common salt is formed by a combination of hydrochloride and sodium hydroxide solution. This is the salt that is used in food. Some salt is called rock salt bed of rack salt was formed when seas of bygone ages dried up. The common salt thus obtained is an important raw material for various materials of daily use, such as sodium hydroxide, baking soda, washing soda, and bleaching powder.

• Phosphoric acid
• Carbonic acid
• Hydrochloric acid
• Sulphuric acid
• Blue vitriol
• Washing soda
• Baking soda
• Bleaching powder

Case-based Question -2

• V 1  + V 2  + V 3
• V 1  – V 2  +V 2
• None of these
• same at every point of the circuit
• different at every point of the circuit
• can not be determined
• 20 3 Ω 203Ω
• 15 2 Ω 152Ω

Case-based Question -3

• pure strips
• impure copper
• refined copper
• none of these
• insoluble impurities
• soluble impurities
• impure metal
• bottom of cathode
• bottom of anode

How to Attempt the Case-Based Questions in Science?

Before answering this question, let’s read the text given in question number 17 of the CBSE Model Question Paper.

All living cells require energy for various activities. This energy is available by the breakdown of simple carbohydrates either using oxygen or without using oxygen.

See, there are only two sentences and CBSE is asking you 5 questions based on these two sentences. Now let’s check the first questions given there.

Energy in the case of higher plants and animals is obtained by a) Breathing b) Tissue respiration c) Organ respiration d) Digestion of food

Now let us know if you can relate the question to the paragraph directly. The two sentences are about energy and how it is obtained. But neither the question nor the options have any similar text in the paragraph.

So the conclusion is, in most cases, you will not get direct answers from the passage. You will get only an idea about the concept. If you know it, you can answer it but reading the paragraph even 100 times is not going to help you.

Test Generator

Create question paper PDF and online tests with your own name & logo in minutes.

Question Bank, Mock Tests, Exam Papers, NCERT Solutions, Sample Papers, Notes

Related Posts

• CBSE Practice Papers 2023
• Class 10 Science Sample Papers 2024
• Competency Based Learning in CBSE Schools
• Class 11 Physical Education Case Study Questions
• Class 11 Sociology Case Study Questions
• Class 12 Applied Mathematics Case Study Questions
• Class 11 Applied Mathematics Case Study Questions
• Class 11 Mathematics Case Study Questions

3 thoughts on “Case Study Questions Class 10 Science”

Where is the answer

Class 10 Science MCQ

Leave a Comment

Save my name, email, and website in this browser for the next time I comment.

• CBSE Study Material
• CBSE Important Questions
• Important Questions For Class 10 Science Chapter 9 Heredity And Evolution

Chapter 9 -Heredity and Evolution

According to the CBSE Syllabus 2023-24, this chapter has been renumbered as Chapter 8 in NCERT Class 10 Science Textbook. 

Students of Class 10 can find the Important Questions for Class 10 Science Chapter 9, Heredity And Evolution, on this page. Students should go through these questions after completing their syllabus. During revision, these important questions will help a lot. Students can easily prepare and boost their exam preparation by practising the important questions provided below. They can also download the pdf of CBSE Class 10 Science Chapter 9, Heredity And Evolution, by clicking on the link below.

Important Questions for Class 10 Science Chapter 9 Heredity And Evolution- Download Free PDF

Leave a Comment Cancel reply

Your Mobile number and Email id will not be published. Required fields are marked *

Request OTP on Voice Call

Post My Comment

Register with BYJU'S & Download Free PDFs

Register with byju's & watch live videos.

• CBSE Class 10

CBSE Class 10 Science Chapter Wise Important Case Study Questions

Chapter wise important case study questions cbse class 10 science: cbse class 10 science board exam 2024 is just around the corner and students are working hard to score maximum marks. check these case study questions from class 10 science to ace your examination this year also download the solutions from the pdf attached towards the end. .

CBSE Class 10 Science Chapter Wise Important Case Study Questions: While the CBSE Board exam for Class 10 students are ongoing, the CBSE Class 10 Science board exam 2024 is to be held on March 2, 2024. With the exams just a  few days away, CBSE Class 10th Board exam candidates are rushing to prepare the remaining syllabus, practising their weak portions, trying to revise the important questions from the past year papers, practise questions, etc. 

Why are CBSE Class 10 Science Case Study Questions Important?

• Section A : 20 Multiple Choice Questions (MCQs) carrying 1 mark each.  
• Section B : 6 Very Short Answer type questions carrying 2 marks each. Answers to these questions should be in the range of 30 to 50 words.  
• Section C : 7 Short Answer type questions carrying 3 marks each. Answers to these questions should be in the range of 50 to 80 words.  
• Section D : 3 Long Answer type questions carrying 5 marks each. Answers to these questions should be in the range of 80 to 120 words.
• Section E : 3 Case Based/ Source Based units of assessment (4 marks each) with sub-parts.  

How to solve case study questions in CBSE Class 10 Science?

• Read the case given and the associated questions carefully.
• Read the questions attentively and analyse what they are asking.
• Apply your subject knowledge and theories in the given case to decide what the correct answers should be.

1.A chemical reaction is a representation of chemical change in terms of symbols and formulae of reactants and products. There are various types of chemical reactions like combination, decomposition, displacement, double displacement, oxidation and reduction reactions. Reactions in which heat is released along with the formation of products are called exothermic chemical reactions. All combustion reactions are exothermic reactions.

(i) The massive force that pushes the rocket forward through space is generated due to the

(a) combination reaction

(b) decomposition reaction

(c) displacement reaction

(d) double displacement reaction

(ii) A white salt on heating decomposes to give brown fumes and yellow residue is left behind. The yellow residue left is of

(a) lead nitrate

(b) nitrogen oxide

(c) lead oxide

(d) oxygen gas

(iii) Which of the following reactions represents a combination reaction?

(a) CaO (s) + H2O (l) → Ca (OH)2 (aq)

(b) CaCO3 (s) → CaO (s) + CO2(g)

(c) Zn(s) + CuSO4 (aq) → ZnSO4 (aq) + Cu(s)

(d) 2FeSO4(s) → Fe2O3 (s) +SO2(g) + SO3(g)

(iv) Complete the following statements by choosing correct type of reaction for X and Y.

Statement 1: The heating of lead nitrate is an example of ‘X’ reaction.

Statement 2: The burning of magnesium is an example of ‘Y’ reaction.

(a)X-Combination,Y-Decomposition

(b)X-Decomposition,Y-Combination

(c)X-Combination,Y-Displacement

(d) X- Displacement, Y-Decomposition

2.The earlier concept of oxidation and reduction is based on the addition or removal of oxygen or hydrogen elements so, in terms of oxygen and hydrogen, oxidation is addition of oxygen to a substance and removal of hydrogen from a substance. On the other hand, reduction is addition of hydrogen to a substance and removal of oxygen from a substance. The substance which gives oxygen to another substance or removes hydrogen from another substance in an oxidation reaction is known as oxidising agent, while the substance which gives hydrogen to another substance or removes oxygen from another substance in a reduction reaction is known as reducing agent. For example, 

(i) A redox reaction is one in which

(a) both the substances are reduced

(b) both the substances are oxidised

(c) an acid is neutralised by the base

(d) one substance is oxidised while the other is reduced.

(ii) In the reaction, H2S+Cl2⟶S+2HCl

(a) H2S is the reducing agent. 

(b) HCl is the oxidising agent.

(c) H2S is the oxidising agent. 

(d) Cl2 is the reducing agent.

(iii) Which of the following processes does not involve either oxidation or reduction?

(a) Formation of slaked lime from quicklime.

(b) Heating mercuric oxide.

(c) Formation of manganese chloride from manganese oxide (MnO2).

(d) Formation of zinc from zinc blende.

(iv) Mg+CuO⟶MgO+Cu

Which of the following is wrong relating to the above reaction?

(a) CuO gets reduced

(b) Mg gets oxidised.

(c) CuO gets oxidised. 

(d) It is a redox reaction.

3.A copper vessel gets tarnished due to formation of an oxide layer on its surface. On rubbing lemon on the vessel, the surface is cleaned, and the vessel begins to shine again. This is due to the fact that which reacts with the acid present in lemon to form a salt which is washed away with water. As a result, the layer of copper oxide is removed from the surface of the vessel and the shining surface is exposed.

1.Which of the following acids is present in lemon?

(a) Formic acid

(b) Acetic acid

(c) Citric acid

(d) Hydrochloric acid

2.The nature of copper oxide is

d) amphoteric

3.Name the salt formed in the above reaction

a) copper carbonate

b) copper chloride

c)copper citrate

d) copper citrate

4.The phenomenon of copper getting tarnished is

a) corrosion

b) rancidity

c) displacement

d)none of these

4.Metals as we know, are very useful in all fields, industries in particular. Non-metals are no less in any way. Oxygen present in air is essential for breathing as well as for combustion. Non-metals form a large number of compounds which are extremely useful, e.g., ammonia, nitric acid, sulphuric acid, etc. Non-metals are found to exist in three states of matter. Only solid non-metals are expected to be hard however, they have low density and are brittle. They usually have low melting and boiling points and are poor conductors of electricity.

i.____________ is a non-metal but is lustrous

A.Phosphorus

ii.Which of the following is known as 'King of chemicals'?

C. Sulphuric acid

D. Nitric acid

iii.Which of the following non-metals is a liquid?

iv.Hydrogen is used

A.for the synthesis of ammonia

B. for the synthesis of methyl alcohol

C.nitrogenous fertilizers

D. all of these

5.Nisha observed that the bottoms of cooking utensils were turning black in colour while the flame of her stove was yellow in colour. Her daughter suggested cleaning the air holes of the stove to get a clean, blue flame. She also told her mother that this would prevent the fuel from getting wasted.

a) Identify the reasons behind the sooty flame arising from the stove.

b) Can you distinguish between saturated and unsaturated compounds by burning them? Justify your answer.

c) Why do you think the colour of the flame turns blue once the air holes of the stove are cleaned?

6.Blood transport food, Oxygen and waste materials in our bodies. It consists of plasma as a fluid medium. A pumping organ [heart] is required to push the blood around the body. The blood flows through the chambers of the heart in a specific manner and direction. While flowing throughout the body, blood exerts a pressure against the wall or a vessel.

• Pulmonary artery
• Pulmonary vein
• Very narrow and have high resistance
• Much wide and have low resistance
• Very narrow and have low resistance
• Much wide and have high resistance
• It is a hollow muscular organ
• It is four chambered having three auricles and one ventricle.
• It has different chambers to prevent O2 rich blood from mixing with the blood containing CO2
• Both A & C
• Blood = Plasma + RBC + WBC + Platelets
• Plasma = Blood – RBC
• Lymph = Plasma + RBC
• Serum = Plasma + RBC + WBC

7.A brain is displayed at the Allen Institute for Brain Science. The human brain is a 3-pound (1.4-kilogram) mass of jelly-like fats and tissues—yet it's the most complex of all known living structures The human brain is more complex than any other known structure in the universe. Weighing in at three pounds, on average, this spongy mass of fat and protein is made up of two overarching types of cells—called glia and neurons— and it contains many billions of each. Neurons are notable for their branch-like projections called axons and dendrites, which gather and transmit electrochemical signals. Different types of glial cells provide physical protection to neurons and help keep them, and the brain, healthy. Together, this complex network of cells gives rise to every aspect of our shared humanity. We could not breathe, play, love, or remember without the brain.

1)Animals such as elephants, dolphins, and whales actually have larger brains, but humans have the most developed cerebrum. It's packed to capacity inside our skulls and is highly folded. Why our brain is highly folded?

• b) Learning

3)Which among these protects our brain?

a)Neurotransmitter

b) Cerebrospinal fluid

d) Grey matter

4.Ram was studying in his room. Suddenly he smells something burning and sees smoke in the room. He rushes out of the room immediately. Was Ram’s action voluntary or involuntary? Why?

8.Preeti is very fond of gardening. She has different flowering plants in her garden. One day a few naughty children entered her garden and plucked many leaves of Bryophyllum plant and threw them here and there in the garden. After few days, Preeti observed that new Bryophyllum plants were coming out from the leaves which fell on the ground.

1.What does the incident sited in the paragraph indicate?

(a). Bryophyllum leaves have special buds that germinate to give rise to new plant.

(b). Bryophyllum can propagate vegetatively through leaves.

(c). Bryophyllum is a flowering plant that reproduces only asexually

(d). Both (a) and (b).

2.Which of the following plants can propagate vegetatively through leaves like Bryophyllum?

3.Do you think any other vegetative part of Bryophyllum can help in propagation? If yes, then which part?

(c) Flowers

4.Which of the following plant is artificially propagated (vegetatively) by stem cuttings in horticultural practices?

(b)Snakeplant

(d)Water hyacinth

9.The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of the population.

1) What are common signs of sexual maturation in boys?

a) Broadening of shoulders

b) Development of mammary glands

c) Broadening of waist

d) High pitch of voice

2) Common sign of sexual maturation in girls is

a) Low pitch voice

b) Appearance of moustache and beard

c) Development of mammary glands

d) Broadening of shoulders

3) Which contraceptive method changes the hormonal balance of the body?

b) Diaphragms

c) Oral pills

d) Both a) and b)

4) What should be maintained for healthy society?

a) Rate of birth and death rate

b) Male and female sex ratio

c) Child sex ratio

d) None of these

10.Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from a plant with wrinkled seeds. The resulting pea pod has all smooth seeds.

i) Which of the following conclusions can be drawn?

(1) The allele for smooth seeds is dominated over that of wrinkled seeds.

(2) The plant with smooth seeds is heterozygous.

(3) The plant with wrinkled seeds is homozygous.

(b) 1 and 2 only

(c) 1 and 3 only

(d) 1, 2 and 3

ii) Which of the following crosses will give smooth and wrinkled seeds in same proportion?

(a) RR X rr

(b) Rr X rr

(d) rr X rr

iii) Which of the following cross can be used to determine the genotype of a plant with dominant phenotype?

(a) RR X RR

(b) Rr X Rr

(c) Rr X RR

(d) RR X rr

iv) On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F1 generation. What will be the respective number of smooth and wrinkled seeds obtained in F1 generation?

(a) 750, 250

(b) 500, 500

(C) 800, 200

(d) 950, 50

11.Food chains are very important for the survival of most species.When only one element is removed from the food chain it can result in extinction of a species in some cases.The foundation of the food chain consists of primary producers.Primary producers or autotrophs,can use either solar energy or chemical energy to create complex organic compounds,whereas species at higher trophic levels cannot and so must consume producers or other life that itself consumes producers. Because the sun’s light is necessary for photosynthesis,most life could not exist if the sun disappeared.Even so,it has recently been discovered that there are some forms of life,chemotrophs,that appear to gain all their metabolic energy from chemosynthesis driven by hydrothermal vents,thus showing that some life may not require solar energy to thrive.

1.If 10,000 J solar energy falls on green plants in a terrestrial ecosystem,what percentage of solar energy will be converted into food energy?

(d)It will depend on the type of the terrestrial plant

2.Matter and energy are two fundamental inputs of an ecosystem. Movement of

(a)Energy is by directional and matter is repeatedly circulating

(b)Energy is repeatedly circulating and matter is unidirectional

(c)Energy is unidirectional and matter is repeatedly circulating

(d)Energy is multidirectional and matter is bidirectional

3.Raj is eating curd/yoghurt. For this food intake in a food chain he should be considered as occupying

(a)First trophic level

(b)Second trophic level

(c)Third trophic level

(d)Fourth trophic level

4.Which of the following, limits the number of trophic levels in a food chain

(a)Decrease in energy at higher trophic levels

(b)Less availability of food

(c)Polluted air

5.The decomposers are not included in the food chain. The correct reason for the same is because decomposers

(a) Act at every trophic level at the food chain

(b) Do not breakdown organic compounds

(c) Convert organic material to inorganic forms

(d) Release enzymes outside their body to convert organic material to inorganic forms

12.Shyam participated in a group discussion in his inter school competition on the practical application of light and was very happy to win an award for his school. That very evening his father gave treat to celebrate Shyam’s win. Shyam while sitting saw an image of a person sitting at his backside in his curved plate and could see that person’s mobile drop in the flower bed. Person was not aware until Shyam went and informed him. He thanked Shyam for his clever move.

a)From which side of his plate Shyam observed the incident –

i)outward curved

ii)inward curved

iii)plane surface

b)Part of plate from which Shyam observed the incident acted like a-

i)concave mirror

ii)convex mirror

iii)plane mirror

c)The nature of the size of the image formed in above situation is –

i)real, inverted and magnified

ii)same size , laterally inverted

iii)virtual, erect and diminished

iv)real , inverted and diminished

d)Magnification of the image formed by convex mirror is –

more than 1

iii)equal to 1

iv)less than 1

• The location of image formed by a convex lens when the object is placed at infinity is

(a) at focus

(c) at optical center

• When the object is placed at the focus of concave lens, the image formed is

(a)real and smaller

(b) virtual and smaller

(c) virtual and inverted

• The size of image formed by a convex lens when the object is placed at the focus ofconvex lens is

(a) highly magnified

(b) point in size

• When the object is placed at 2F in front of convex lens, the location of image is

(b) between F and optical center

(c) at infinity

(d) none of the above

14.One of the wires in domestic circuits supply, usually with a red insulation cover, is called live wire. with black insulation is called neutral wire. The earth wire, which has insulation of green colour, is usually connected to a metal plate deep in the earth near the house appliances that has a metallic body. Overloading contact, in such a situation the current in the circuit abruptly increases. circuit prevents damage to the appliances and the circuit due to overloading.

1 When do we say that an electrical appliance

2 Mention the function of earth wire in electrical line

3 How is an electric fuse connected in a domestic circuit?

4 When overloading and short circuiting are said to occur?

5 What is a live wire?

15.Light of all the colours travel at the same speed in vacuum for all wavelengths. But in any transparent medium(glass or water), the light of different colours travels at different speeds for different wavelengths, which means that the refractive index of a particular medium is different for different wavelengths. As there is a difference in their speeds, the light of different colours bend through different angles. The speed of violet colour is maximum and the speed of red colour is minimum in glass so, the red light deviates least and violet colour deviates most. Hence, higher the wavelength of a colour of light, smaller the refractive index and less is the bending of light.

(i)Which of the following statements is correct regarding the propagation of Light of different colours of white light in air?

(a) Red light moves fastest.

(b) Blue light moves faster than green light.

(c) All the colours of the white light move with the same speed.

(d) Yellow light moves with the mean speed as that of the red and the violet light.

(ii)Which of the following is the correct order of wavelength?

(a) Red> Green> Yellow

(b) Red> Violet> Green

(c) Yellow> Green> Violet

(d) Red> Yellow> Orange

(iii)Which of the following is the correct order of speed of light in glass?

(a) Red> Green> Blue

(b) Blue> Green> Red

(c) Violet> Red> Green

(d) Green> Red> Blue

(iv)Which colour has maximum frequency?

16.The region around a magnet where magnetism acts is represented by the magnetic field.The force of magnetism is due to moving charge or some magnetic material. Like stationary charges produce an electric field proportional to the magnitude of charge, moving charges produce magnetic fields proportional to the current. In other words, a current carrying conductor produces a magnetic field around it. The subatomic particles in the conductor, like the electrons moving in atomic orbitals, are responsible for the production of magnetic fields. The magnetic field lines around a straight conductor (straight wire) carrying current are concentric circles whose centres lie on the wire.

1)The magnetic field associated with a current carrying straight conductor is in anti- clockwise direction. If the conductor was held horizontally along east west direction,what is the direction of current through it?

2)Name and state the rule applied to determine the direction of magnetic field in a straight current carrying conductor.

3)Ramus performs an experiment to study the magnetic effect of current around a current carrying straight conductor with the help of a magnetic compass. He reports that

a)The degree of deflection of magnetic compass increases when the compass is moved away from the conductor.

b)The degree of deflection of the magnetic compass increases when the current through the conductor is increased.

Which of the above observations of the student appears to be wrong and why?

Case Study Questions Class 10 Science CBSE Chapter Wise PDF

Related resources to prepare for CBSE 10th Science Board Exam 2024

• CBSE class 10 Science syllabus 2024
• NCERT Book for Class 10th Science 2023-2024 (PDF)
• NCERT Solutions for Class 10 Science  
• CBSE Class 10 Science sample paper  
• Previous Year Questions of CBSE Class 10 Science
• CBSE Class 10 Science Important Questions and Answers
• CBSE Class 10 Physics Chapter Wise Important Questions and Answers
• CBSE Class 10 Chemistry Chapter Wise Important Questions and Answers
• CBSE Class 10 Biology Chapter Wise Important Questions and Answers
• CBSE Class 10 Science Topper Answer Sheet
• CBSE Class 10 Science Practice Paper 2023 with Answers
• Class 10 CBSE Admit Card 2023-24
• CBSE Class 10 Date Sheet 2023
• CBSE Class 10 Syllabus 2023 - 2024
• CBSE Class 10 DELETED Syllabus 2023-24
• CBSE Class 10th Sample Paper 2022-23: Download Sample Question Papers and Marking Scheme
• CBSE Class 10 Previous Year Question Papers for 2022-23
• CBSE Class 10 Important Questions and Answers for 2023-24 of ALL Chapters
• CBSE Class 10 Practice Papers: All Subjects
• CBSE Topper Answer Sheet Class 10: Model Answer Paper Download PDF
• CBSE Class 10 Mock Tests: All Subjects

Get here latest School , CBSE and Govt Jobs notification and articles in English and Hindi for Sarkari Naukari , Sarkari Result and Exam Preparation . Download the Jagran Josh Sarkari Naukri App .

• CTET Result 2024
• UGC NET Admit Card 2024
• AFCAT Admit Card 2024
• IBPS RRB Exam Analysis 2024
• UPSC CAPF Exam Analysis 2024
• UPSC CAPF Question Paper 2024
• SSC CHSL Answer Key 2024
• IBPS RRB PO Exam Review 2024
• India Post GDS Cut Off
• CBSE Class 10 QnA

Latest Education News

Henley Passport Index 2024: दुनिया में किस देश का है सबसे ताकतवर पासपोर्ट और क्या है भारत का स्थान, जानें

UP DElED Admit Card 2024 OUT at btcexam.in; Direct Link to Download Semester Exam Hall Ticket PDF

Deepest Lake in USA: List of the Top 10 Deepest Lakes in America

Celsius to Kelvin: Concept, Formula and Key Difference

Today Current Affairs One Liners: 05 August 2024- Bangladesh PM Sheikh Hasina Quits

RPSC ASO Recruitment 2024: Apply Online for 43 Assistant Statistical Officer Vacancies

RSMSSB LDC Admit Card Date 2024 Released: Check Your Jr Assistant Exam City Details Here

MGSU Admit Card 2024 OUT; Direct Link to Download UG Hall Ticket PDF

RSMSSB LDC, Jr Assistant Admit Card 2024 OUT: राजस्थान एलडीसी और जूनियर असिस्टेंट परीक्षा के एडमिट कार्ड जारी, ये रहा डाउनलोड लिंक

Top 5 Govt Jobs of the Day-Aug 05, 2024: Apply Online for 4000+ Posts @SSC, RPSC, HPSC, AIIMS NORCET and others

CBSE 10th Compartment Result 2024 OUT: CBSE 10th Supplementary Results Announced at cbseresults.nic.in, Check by Roll and School Number

Today Current Affairs Quiz: 05 August 2024- Paris Olympics 2024

Gauhati University Result 2024 OUT at guportal.in; Direct Link to Download UG and PG Marksheet

UPSC CAPF Expected Cut Off 2024: Check Minimum Qualifying Marks

CSAB Counselling 2024: Special Round 1 Seat Allotment Out, Download at csab.nic.in

KIIT DU Awarded Prestigious UN ECOSOC Special Consultative Status

Allahabad University Admission 2024 Registration Close Today, Apply at alldunivcuet.samarth.edu.in

Today Current Affairs Hindi One Liners: 05 अगस्त 2024- नेशनल हाई-स्पीड रोड कॉरिडोर

MSBU Result 2024 OUT at msbuexam.in, Direct Link to Download UG and PG Marksheet

HSSC CET Admit Card 2024 OUT at hssc.gov.in: Download Haryana Group C Mains Hall Ticket Here

• Andhra Pradesh
• Chhattisgarh
• West Bengal
• Madhya Pradesh
• Maharashtra
• Jammu & Kashmir
• NCERT Books 2022-23
• NCERT Solutions
• NCERT Notes
• NCERT Exemplar Books
• NCERT Exemplar Solution
• States UT Book
• School Kits & Lab Manual
• NCERT Books 2021-22
• NCERT Books 2020-21
• NCERT Book 2019-2020
• NCERT Book 2015-2016
• RD Sharma Solution
• TS Grewal Solution
• TR Jain Solution
• Selina Solution
• Frank Solution
• Lakhmir Singh and Manjit Kaur Solution
• I.E.Irodov solutions
• ICSE - Goyal Brothers Park
• ICSE - Dorothy M. Noronhe
• Micheal Vaz Solution
• S.S. Krotov Solution
• Evergreen Science
• KC Sinha Solution
• ICSE - ISC Jayanti Sengupta, Oxford
• ICSE Focus on History
• ICSE GeoGraphy Voyage
• ICSE Hindi Solution
• ICSE Treasure Trove Solution
• Thomas & Finney Solution
• SL Loney Solution
• SB Mathur Solution
• P Bahadur Solution
• Narendra Awasthi Solution
• MS Chauhan Solution
• LA Sena Solution
• Integral Calculus Amit Agarwal Solution
• IA Maron Solution
• Hall & Knight Solution
• Errorless Solution
• Pradeep's KL Gogia Solution
• OP Tandon Solutions
• Sample Papers
• Previous Year Question Paper
• Important Question
• Value Based Questions
• CBSE Syllabus
• CBSE MCQs PDF
• Assertion & Reason
• New Revision Notes
• Revision Notes
• Question Bank
• Marks Wise Question
• Toppers Answer Sheets
• Exam Paper Aalysis
• Concept Map
• CBSE Text Book
• Additional Practice Questions
• Vocational Book
• CBSE - Concept
• KVS NCERT CBSE Worksheets
• Formula Class Wise
• Formula Chapter Wise
• JEE Previous Year Paper
• JEE Mock Test
• JEE Crash Course
• JEE Sample Papers
• Important Info
• SRM-JEEE Previous Year Paper
• SRM-JEEE Mock Test
• VITEEE Previous Year Paper
• VITEEE Mock Test
• BITSAT Previous Year Paper
• BITSAT Mock Test
• Manipal Previous Year Paper
• Manipal Engineering Mock Test
• AP EAMCET Previous Year Paper
• AP EAMCET Mock Test
• COMEDK Previous Year Paper
• COMEDK Mock Test
• GUJCET Previous Year Paper
• GUJCET Mock Test
• KCET Previous Year Paper
• KCET Mock Test
• KEAM Previous Year Paper
• KEAM Mock Test
• MHT CET Previous Year Paper
• MHT CET Mock Test
• TS EAMCET Previous Year Paper
• TS EAMCET Mock Test
• WBJEE Previous Year Paper
• WBJEE Mock Test
• AMU Previous Year Paper
• AMU Mock Test
• CUSAT Previous Year Paper
• CUSAT Mock Test
• AEEE Previous Year Paper
• AEEE Mock Test
• UPSEE Previous Year Paper
• UPSEE Mock Test
• CGPET Previous Year Paper
• Crash Course
• Previous Year Paper
• NCERT Based Short Notes
• NCERT Based Tests
• NEET Sample Paper
• Previous Year Papers
• Quantitative Aptitude
• Numerical Aptitude Data Interpretation
• General Knowledge
• Mathematics
• Agriculture
• Accountancy
• Business Studies
• Political science
• Enviromental Studies
• Mass Media Communication
• Teaching Aptitude
• Verbal Ability & Reading Comprehension
• Logical Reasoning & Data Interpretation
• CAT Mock Test
• CAT Vocabulary
• CAT English Grammar
• CMAT Mock Test
• SRCC GBO Mock Test
• SRCC GBO PYQs
• XAT Mock Test
• SNAP Mock Test
• IIFT Mock Test
• MAT Mock Test
• CUET PG Mock Test
• CUET PG PYQs
• MAH CET Mock Test
• MAH CET PYQs
• NAVODAYA VIDYALAYA
• SAINIK SCHOOL (AISSEE)
• Mechanical Engineering
• Electrical Engineering
• Electronics & Communication Engineering
• Civil Engineering
• Computer Science Engineering
• CBSE Board News
• Scholarship Olympiad
• School Admissions
• Entrance Exams
• All Board Updates
• Miscellaneous
• State Wise Books
• Engineering Exam

Heredity and Evolution Class 10 NCERT Solutions PDF Download

It is advisable for all the students to go through the Heredity and Evolution Class 10 NCERT Solutions if they want to perform well in their examinations. These NCERT Solutions are very common among the students. From easy to hard, these Solutions consist of all the types of Solutions which can help the students to get an idea of the concept and boost their conceptual knowledge. The students also get the idea about the overall exam pattern. 

If a student wants to do effective preparation for their exam, then they can go for the Class 10 Heredity and Evolution NCERT Solutions without any doubt. Our highly qualified subject matter experts at Selfstudys have created these Solutions to help the students understand each and every topic in a detailed manner. They are also aware of the learning potential of every student that is why they have created these Solutions in an easy to understand manner. The students can also use these Solutions for revision as they cover each and every topic which can update the students about their progress. 

The Heredity and Evolution Class 10 NCERT Solutions can be downloaded from the website of Selfstudys i.e. Selfstudys.com. In this article below, we will discuss a lot of things about these Solutions including how you can download them, their features, benefits, Tips to master them and Frequently Asked Questions. 

Heredity and Evolution Class 10 NCERT Solutions PDF 

The Class 10 Heredity and Evolution NCERT Solutions are developed in the PDF Format which can be easily downloaded from the website of Selfstudys i.e. Selfstudys.com. The PDF can be easily downloaded and can be shared in laptop, mobile etc. 

How to Download the Heredity and Evolution Class 10 NCERT Solutions?

Downloading the Class 10 Heredity and Evolution NCERT Solutions is if you know the right steps. It is just a matter of 2 minutes. The steps to download them are as follows: 

• Go to the official website of Selfstudys i.e. Selfstudys. 

• Once the website is completely loaded, you need to click on the three lines which you will find on the upper left side. Following that, you have to click on the ‘NCERT Books and Solutions’.

• After clicking on the option of ‘NCERT Books and Solutions’, a new list will open and you need to select the option of ‘NCERT Solutions’.

• After that, you will be redirected to a page where you need to select the class and subject for which you want to download the Solutions.
• Here, you need to select class 10 and subject Science to download the Class 10 Heredity and Evolution NCERT Solutions. 
• And that’s it! It was this simple to download the Heredity and Evolution Class 10 NCERT Solutions. 

What Are the Features of Class 10 Heredity and Evolution NCERT Solutions?

There are many features of the NCERT Solutions Class 10 Science Heredity and Evolution which can be very beneficial for all the students. Some of the most important of them which helps the students to score good marks in their exams consists of the following features: 

• Simple Language used in the Solutions: The language used in the Class 10 Heredity and Evolution NCERT Solutions is simple which can help a lot of students to grasp and memorise the concepts fastly. This ensures that the student has prepared well and will do well in their exams. 
• Easy Access: The Class 10 Heredity and Evolution NCERT Solutions can be easily downloaded from the website of Selfstudys in the PDF Format which makes it easier for them to access it. Students can also access them on their mobile phones. 
• Every single topic is covered: Each and every topic is covered in the Heredity and Evolution Class 10 NCERT Solutions which not only helps the students to prepare well for the exams but also helps them make them motivated that they will score good marks in their exams. 
• High Order Questions are also included: In the Heredity and Evolution Class 10 NCERT Solutions, the HOTS (High Order Thinking Skills) are also included which forces the students to think logically. This not only helps the students to do effective revision but also boosts their logical thinking skills. 
• 24*7 Available Online: The Class 10 Heredity and Evolution NCERT Solutions are available 24*7 Online which can be easier for all the students whether they want to study during the day or at night. It is beneficial for students who study late at night. 

What Are the Advantages of Heredity and Evolution Class 10 NCERT Solutions?

There are many advantages of NCERT Solutions Class 10 Heredity and Evolution which can be highly beneficial for all the students. Some of the most important of them which increases their conceptual knowledge includes: 

• Helps in Solving HOTS Questions: The students will find various questions while doing the preparation for their exams. Most of them are high-order thinking skills also which require no distraction. The Class 10 Heredity and Evolution NCERT Solutions helps all the students to solve high-level questions easily and fast. It also helps in boosting the conceptual knowledge of all the students. 
• Improves Speed of the students: Due to the well-detailed nature of the NCERT Solutions Class 10 Heredity and Evolution, it helps the students to understand them and also improves the speed of the students. 
• Recommended by the CBSE (Central Board of Secondary Education): The CBSE Itself recommends all the students to go through the Heredity and Evolution Class 10 NCERT Solutions. According to CBSE, for a student to prepare well and score good marks in the exams, NCERT Solutions are enough. 
• Helpful in Revision: As revision helps recall all the details of the topic which you have studied, it is advisable for all of you to revise all the concepts after studying them. It also helps to remember the concepts for a longer period of time. Class 10 Heredity and Evolution NCERT Solutions helps to revise all the concepts in an effective manner. 
• Time Management: It is suggested for all the students to take care of the time management as it helps them to work with higher productivity and manage their time effectively during the exam time. With time management, things are simpler and easier for all the students. 

What Are the Tips to Study From Heredity and Evolution Class 10 NCERT Solutions?

There are various tips which can help the students to study effectively from the NCERT Solutions Class 10 Heredity and Evolution : 

• Take Mini Breaks: When studying from the Class 10 Heredity and Evolution NCERT Solutions, it is advisable for all the students to take short Heredity and Evolution Class 10 NCERT Solutions breaks as it will ensure that they are doing effective preparation. According to the research, a break of half an hour in between the study sessions keeps the students calm during the exam days where the chances of getting stressed and anxious is more.
• Stay Focused: Keeping your mind stable is very important for all the students during exam days. They should distance themselves from mobile phones and outings to remain focused in their work. While studying NCERT Solutions Class 10 Heredity and Evolution, they should stay focused to grasp the concepts easily. 
• Practise the Solved Examples: After understanding the basic concept, you can start practising the Heredity and Evolution Class 10 NCERT Solutions examples which are present in the NCERT Solutions. This will give you an idea about the types of problems which have high chances of appearing in the exams. 
• Revise Regularly: Do not forget to revise the chapter thoroughly as it helps in remembering the concepts for a longer period of time. They will also get to know about their stronger and weaker areas and they will be able to improve that accordingly. 
• Study in a group: Studying in a group can be really beneficial for you as you discuss various concepts and topics from the Class 10 Heredity and Evolution NCERT Solutions with your peers. It can also motivate you and will help you in getting a clear understanding of each and every topic. 

What Are the Methods to Study From Heredity and Evolution Class 10 NCERT Solutions? 

Studying for the Science exam requires focus and concentration. Below we will discuss various methods how students can study for a Science Exam with the help of Heredity and Evolution Class 10 NCERT Solutions: 

• Understand the basics: The first tip to study for a Science exam with the help of Heredity and Evolution Class 10 NCERT Solutions is to understand the basics as it will make it easier to study further. 
• Read through the chapter thoroughly: After learning about the basics of the Heredity and Evolution, the students should read through the entire chapter and try to learn the key concepts and definitions. This will help in boosting the conceptual knowledge of all the students. 
• Study Class 10 Heredity and Evolution NCERT Solutions on a regular basis: Students are advised to study Heredity and Evolution Class 10 NCERT Solutions regularly either on a weekly basis or they should decide as per their convenience. It will help the students to stick the concepts in their minds and help them to do effective preparation. It also increases their chances of scoring good marks in the exams. 
• Read the summary of your textbook: There is always a summary in your textbook which is advisable for the students to go through as it will help them to boost their conceptual knowledge and helps them to prepare well for their exams. 

How to Master Heredity and Evolution Class 10 NCERT Solutions? 

There are various ways to master Heredity and Evolution Class 10 NCERT Solutions . Some of the most important of them are: 

• Use the NCERT Solutions: If you want to master the Heredity and Evolution, then you should regularly use these NCERT Solutions to improve your conceptual knowledge. 
• Do regular practice of the NCERT Solutions: The students are advised to do regular practice of Class 10 Heredity and Evolution NCERT Solutions as it helps the students to prepare well for their exams. Regular practice will also help the students to master their conceptual knowledge. 
• Apply the 80/20 Principle: The students can apply the 80/20 principle while going through Heredity and Evolution Class 10 NCERT Solutions. The principle means looking at the bigger picture of what students are trying to memorise and evaluating which 20% of the concepts within it will bring you the advantage of the 80%. 

How to Apply the 80/20 Principle While Going Through the Heredity and Evolution Class 10 NCERT Solutions?

The 80/20 principle can also be applied while studying to maximise your productivity and efficiency. Here are some ways to apply the 80/20 principle while studying:

• Identify the important topics: It is advisable for all the students to Identify the 20% of topics or concepts from the Class 10 Heredity and Evolution NCERT Solutions that are most important for the exam and focus on studying those first. These are usually the topics that carry high weightage in the exams. 
•  Prioritise your study time: After identifying the most important topics from the Heredity and Evolution Class 10 NCERT Solutions, the students should prioritise their study time accordingly. Spend more time studying the most important topics and less time on the less important ones. This will help you maximise your study time and make the most out of it. 
• Focus on the quality of study time: Instead of investing a long time studying the NCERT Solutions Class 10 Heredity and Evolution, students should focus on the quality of their study time. Take short breaks as mentioned earlier in this article, make strategies, and minimise distractions to ensure that you are able to prepare well for the exam. 
• Analyse your study habits : Analyse your study habits to identify the 20% of habits that are most effective in helping you memorise the concepts and retain information. Focus on these habits and try to eliminate the less effective ones to improve your overall study efficiency. 

• NCERT Solutions for Class 12 Maths
• NCERT Solutions for Class 10 Maths
• CBSE Syllabus 2023-24
• Social Media Channels
• Login Customize Your Notification Preferences

One Last Step...

• Second click on the toggle icon

Provide prime members with unlimited access to all study materials in PDF format.

Allow prime members to attempt MCQ tests multiple times to enhance their learning and understanding.

Provide prime users with access to exclusive PDF study materials that are not available to regular users.

Project On Heredity And Evolution For Class 10

Table of Contents

Introduction

Heredity and evolution are the bedrock of biological knowledge, enabling us to grasp the unbroken thread of life and the ever-changing tapestry it weaves. Heredity ensures the seamless transfer of genetic information from one generation to the next, while evolution accounts for the gradual metamorphosis of species. These principles underpin the rich biodiversity on our planet and the intricate mechanisms that govern the continuum of life.

The mission of this project is to embark on a deep dive into heredity and evolution, with a keen focus on their profound importance in the realm of biology. Our all-encompassing approach, blending meticulous research, engaging presentations, insights from experts, and the option for hands-on experiments, guarantees a holistic grasp of these fundamental concepts.

Materials and Methods: Our methods are as diverse as the subject matter itself. We’ve cast a wide net, drawing information from textbooks, online sources, and the latest scientific journals to ensure our findings are both robust and up-to-date. Interviews with experts bring real-world perspectives to our work, while the inclusion of experiments, such as the use of Punnett squares to explore genetic inheritance, offers a tangible, accessible understanding of complex concepts.

Definition: Heredity encapsulates the intricate process by which genetic traits and information flow from one generation to the next. Role of DNA: DNA, the guardian of genetic data, plays a pivotal role, carrying the legacy of our ancestors and transmitting it through the ages. Mendel’s Laws: The groundbreaking laws of inheritance, as elucidated by Gregor Mendel and illustrated with the aid of Punnett squares, provide a structured framework for understanding the mechanics of genetic transmission. Genetic Traits and Variations: We delve into genetic traits and the myriad variations that arise within populations, underscoring the diverse tapestry that fuels the engine of evolution.

Definition: Evolution is the dynamic dance of species transformation over time, choreographed by natural selection and environmental forces. Natural Selection: The concept of natural selection, articulated by Charles Darwin, stands as a cornerstone in deciphering the choreography of evolutionary change. Evidence of Evolution: The rich tapestry of evidence, from the fossil record to comparative anatomy and molecular biology, paints a vivid portrait of evolution as a fundamental biological tenet. Examples of Evolution: Real-world stories, such as the adaptation of the peppered moth and the ever-changing beaks of Galapagos finches, breathe life into the concept of evolution in action.

Interconnection

Relationship Between Heredity and Evolution: We explore how heredity acts as the bridge linking genetic variation, serving as the raw material essential for the ongoing evolutionary symphony. Role of Mutations: This section sheds light on how genetic mutations introduce variations, propelling the process of evolution and turning each generation into a repository of potential change. Adaptation and Survival: By highlighting how variations within species lead to adaptation and enhance survival prospects in shifting environments, we celebrate the dynamic and responsive nature of life.

Case Studies

Species Evolution: Through captivating case studies of specific species that have evolved due to environmental shifts or genetic variations, we offer concrete evidence of life’s perpetual transformation. Fossil Records: We unearth the importance of the fossil record in reconstructing the ancient history of life on Earth, a story of eons in the making.

Human Evolution

Human Origins: We trace the evolutionary odyssey of humans, from early hominids to modern Homo sapiens, spotlighting our place in the grand narrative of evolution. Cultural and Biological Evolution: The interplay between cultural and biological evolution in shaping the human species reveals the intricate interweaving of factors that have shaped our present form.

This section serves as a compass, guiding us through the project’s findings. It reinforces the paramount importance of comprehending heredity and evolution and emphasizes their inextricable interplay in shaping life’s intricate web.

In conclusion, we seamlessly weave together the twin pillars of heredity and evolution, accentuating their indivisible bond. Heredity ensures the unbroken transmission of genetic information, while evolution represents the ever-evolving tale of species. These concepts are intrinsically connected, with heredity laying the foundation for the genetic diversity that propels the grand narrative of evolution.

The understanding of heredity and evolution is key to unraveling the complexity and diversity of life on our planet, as well as the intricate mechanisms governing the development and adaptation of species. Through this project, we’ve illuminated these foundational biological concepts, laying a sturdy groundwork for further exploration and understanding.

Certificate of Completion

This is to certify that I, [Student’s Name], a [Class/Grade Level] student, have successfully completed the project on “Heredity And Evolution For Class 10.” The project explores the fundamental principles and key aspects of the chosen topic, providing a comprehensive understanding of its significance and implications.

In this project, I delved into in-depth research and analysis, investigating various facets and relevant theories related to the chosen topic. I demonstrated dedication, diligence, and a high level of sincerity throughout the project’s completion.

Key Achievements:

Thoroughly researched and analyzed Project On Heredity And Evolution For Class 10. Examined the historical background and evolution of the subject matter. Explored the contributions of notable figures in the field. Investigated the key theories and principles associated with the topic. Discussed practical applications and real-world implications. Considered critical viewpoints and alternative theories, fostering a well-rounded understanding. This project has significantly enhanced my knowledge and critical thinking skills in the chosen field of study. It reflects my commitment to academic excellence and the pursuit of knowledge.

In order to download the PDF, You must follow on Youtube. Once done, Click on Submit

Subscribed? Click on Confirm

Download Project On Heredity And Evolution For Class 10 PDF

Related articles.

Automated Roti and Puri Maker Press project

The Oil Skimmer RC Boat

Secure Digi Locker Application Project

Software Piracy Protection Project

Leave a reply cancel reply.

Your email address will not be published. Required fields are marked *

Please Enable JavaScript in your Browser to Visit this Site.