Science and Technology II · Textbook solutions

Heredity and Evolution

Every solved example, exercise, and miscellaneous question, in the order the textbook teaches them. Plus every board question asked from this chapter. · 22 questions

Exercise

22 q

Ex Q1 $Complete the following diagram.$
Read the following statements and justify the same in your own words with the help of suitable examples.
Ex Q2(a) $Human evolution began approximately 7 crore years ago.$
Ex Q2(b) $Geographical and reproductive isolation of organisms gradually leads to speciation.$
Ex Q2(c) $Study of fossils is an important aspect of study of evolution.$
Ex Q2(d) $There is evidence of fatal science among chordates.$
Complete the statements by choosing correct options from bracket. (Gene, Mutation, Translocation, Transcription, Gradual development, Appendix)
Ex Q3(a) $The causality behind the sudden changes was understood due to -- -- principle of Hugo de Vries.$
Ex Q3(b) $The proof for the fact that protein synthesis occurs through -- --- was given by George Beadle and Edward Tatum.$
Ex Q3(c) $Transfer of information from molecule of DNA to mRNA is called as -- -- -- process.$
Ex Q3(d) $Evolution means -- -- -- --.$
Ex Q3(e) $Vestigial organ -- -- -- present in human body is proof of evolution.$
Write short notes based upon the information known to you.
Ex Q4(a) $Lamarckism$
Ex Q4(b) $Darwin's theory of natural selection.$
Ex Q4(c) $Embryology.$
Ex Q4(d) $Evolution.$
Ex Q4(e) $Connecting link.$
Ex Q6 $Define vestigial organs. Write names of some vestigial organs in human body and write the names of those animals in whom same organs are functional.$
Answer the following questions.
Ex Q7(a) $How are the hereditary changes responsible for evolution?$
Ex Q7(b) $Explain the process of formation of complex proteins.$
Ex Q7(c) $Explain the theory of evolution and mention the proof supporting it.$
Ex Q7(d) $Explain with suitable examples importance of anatomical evidences in evolution.$
Ex Q7(e) $Define fossil. Explain importance of fossils as proof of evolution.$
Ex Q7(f) $Write evolutionary history of modern man.$

What the board has asked from this chapter

Questions per paper · 13 papers · 2016 to 2026

June 2026

3 q

Q1(A)(i) $‘देवमाशाचा पर’ हा ____ विषयक पुरावा आहे. Flipper of whale is ____________ type of evidence of evolution.$
Tap an option to check your answer.
Speciation and Evidences of Evolution
Q2(A)(i) $शास्त्रीय कारणे लिहा : पेरीपॅटस हा ॲनेलिडा व संधिपाद प्राणी या दोघांना जोडणारा दुवा आहे. Give scientific reason: Peripatus is connecting link between Annelida and Arthropoda.$
Speciation and Evidences of Evolution
Q3(i) $खालील आकृती पूर्ण करा : उत्क्रांतीचे पुरावे : शरीरशास्त्रीय पुरावे, ____, ____, ____Complete the following diagram: (Concept map 'Evidences of Evolution' with four boxes: Anatomical, ____________, ____________, ____________.)$
Speciation and Evidences of Evolution

March 2026

3 q

Q1(A)(i) $अचानक घडणाऱ्या बदलांमागील कार्यकारण भाव ह्युगो द व्ह्रीस यांच्या ____ सिद्धांतामुळे लक्षात आला. The causality behind the sudden changes was understood due to ____________ principle of Hugo de Vries.$
Tap an option to check your answer.
Evolution and its Theories
Q2(B)(i) $कार्बनी वयमापनाची व्याख्या लिहून त्याचा एक उपयोग लिहा. What is meant by carbon dating? Give any one use of this technique.$
Speciation and Evidences of Evolution
Q3(i) $लॅमार्कवाद सिद्धांत लिहून तो दोन उदाहरणांद्वारे स्पष्ट करा. Explain the theory of Lamarckism with the help of any two suitable examples.$
Evolution and its Theories

July 2025

3 q

Q1(B)(i) $चूक की बरोबर ते लिहा : उत्क्रांती म्हणजे सजीवांमध्ये अत्यंत सावकाश होणारा क्रमिक बदल होय. State whether the following statement is True or False: Evolution is the gradual change occurring in living organisms over a long duration.$
Evolution and its Theories
Q2(B)(i) $आकृतीत दिलेल्या प्राण्यांचे निरीक्षण करून प्रश्नांची उत्तरे लिहा : (अ) वरील आकृतीत दिलेले प्राणी ओळखा. (ब) वरील प्राणी उत्क्रांतीच्या कोणत्या पुराव्याची उदाहरणे आहेत ? Observe the given animals (Fig. A and Fig. B) and answer the questions: (a) Identify the animals shown in above figure. (b) State the type of evidence of evolution related to above animals.$
Speciation and Evidences of Evolution
Q3(iii) $खालील प्रश्नांची उत्तरे लिहा : (अ) अवशेषांग म्हणजे काय ? (आ) मानवी शरीरातील दोन अवशेषांगांची नांवे लिहा. (इ) मानवासाठी निरुपयोगी परंतु इतर प्राण्यांसाठी उपयुक्त व कार्यक्षम असलेल्या दोन अवशेषांगांची नावे लिहा. Answer the following questions: (a) Define vestigial organs. (b) Write names of any two vestigial organs in human body. (c) Write the names of any two vestigial organs which are non-functional in human beings but functional in other organisms.$
Speciation and Evidences of Evolution

March 2025

3 q

Q1(A)(iii) $जनुकांमध्ये अचानक बदल होवून सजीवात लहानसा बदल घडून येतो. तो बदल म्हणजेच ____ होय. Any nucleotide of the gene suddenly changes its position that causes a minor change which is nothing but the ____.$
Tap an option to check your answer.
Heredity and Variation
Q1(B)(iii) $चूक की बरोबर, ते लिहा : जीवाश्मांचा अभ्यास हे उत्क्रांतीच्या अभ्यासाचे एक महत्त्वाचे अंग आहे. State whether true or false: Study of fossils is an important aspect of the study of evolution.$
Speciation and Evidences of Evolution
Q3(i) $आनुवंशिकता म्हणजे काय हे स्पष्ट करून आनुवंशिक बदल कसे घडतात ते स्पष्ट करा. Define heredity. Explain the mechanism of hereditary changes.$
Heredity and Variation

July 2024

2 q

Q1(A)(i) $उत्क्रांती म्हणजेच ____ होय. Evolution means ____.$
Tap an option to check your answer.
Evolution and its Theories
Q3(ii) $(अ) अवशेषांगे म्हणजे काय ? (आ) मानवी शरीरातील दोन अवशेषांगाची नावे लिहा. (इ) मानवी शरीरातील अवशेषांगे इतर कोणत्या प्राण्यांसाठी कशी उपयुक्त आहेत ? त्याची दोन उदाहरणे द्या. (a) What are vestigial organs? (b) Write two names of some vestigial organs in human body. (c) Write the names of those animals in whom same organs are used? Give two examples.$
Speciation and Evidences of Evolution

March 2024

3 q

Q1(A)(iii) $जनुकातील एखादे न्युक्लिओटाईड अचानक आपली जागा बदलते, यामुळे जो लहानसा बदल घडून येतो त्या बदलाला ____ असे म्हणतात. A minor change that occurs due to a change in the position of any nucleotide is termed as ____.$
Tap an option to check your answer.
Heredity and Variation
Q1(B)(v) $44 + XX$
Heredity and Variation
Q3(vii) $(अ) अवशेषांगे म्हणजे काय ? (ब) मानवी शरीरातील कोणत्याही दोन अवशेषांगांची नावे लिहा. (क) तीच अवशेषांगे इतर कोणत्याही प्राण्यांसाठी कशी उपयुक्त आहेत ते लिहा. (a) Define vestigial organs. (b) Write the names of any two vestigial organs in the human body. (c) Write the name of those animals in which these vestigial organs are functional.$
Speciation and Evidences of Evolution

March 2023

2 q

Q1(A)(i) $Vestigial organ ____ present in human body is proof of evolution.$
Tap an option to check your answer.
Speciation and Evidences of Evolution
Q3(i) $Explain Darwin's theory of natural selection.$
Evolution and its Theories

March 2022

2 q

Q2(B)(i) $Complete the following diagram (chart of 'Evidences of Evolution' — two boxes, 'Morphological' and 'Similarities in bone structure', are given and four boxes are blank).$
Speciation and Evidences of Evolution
Q3(vi) $Write the objections raised against Darwin's theory of natural selection.$
Evolution and its Theories

March 2020

2 q

Q1(A)(i) $Transfer of information from molecule of DNA to mRNA is called ____ process.$
Tap an option to check your answer.
Heredity and Variation
Q3(i) $Explain the importance of Anatomical evidences with examples.$
Speciation and Evidences of Evolution

March 2019

6 q

Q1(B)(v) $____________ is a connecting link between annelida and arthropoda.$
Tap an option to check your answer.
Speciation and Evidences of Evolution
Q2(i) $Complete the following chart:$
Speciation and Evidences of Evolution
Q3(i)(a) $What do you mean by central dogma?$
Heredity and Variation
Q3(i)(b) $What is transcription?$
Heredity and Variation
Q3(i)(c) $What is meant by triplet codon?$
Heredity and Variation
Q4(ii)(a) $'Gender of a child is determined by the male partner of a couple.' Draw a diagram explaining the above statement.$
Heredity and Variation

March 2018

4 q

Q1(A)(a)(i) $Rewrite the following statement with a suitable word in the blank: There are ______ pairs of chromosomes in human being.$
Heredity and Variation
Q1(A)(b)(i) $State whether the following statement is true or false: There are two sets of chromosomes in zygote.$
Heredity and Variation
Q3(2) $Human tail bone is a vestigial organ. Explain.$
Speciation and Evidences of Evolution
Q3(6) $How is sex determined in the human beings?$
Heredity and Variation

March 2017

4 q

Fill in the blanks and rewrite the completed statements.
Q1(A)(1)(ii) $Both the parents contribute equal amount of ______ material to the offspring.$
Heredity and Variation
Attempt any five of the following.
Q2(2) $Differentiate between Mendel's monohybrid cross and dihybrid cross.$
Mendel's Laws of Inheritance
Q2(5) $What are vestigial organs? Give one example.$
Speciation and Evidences of Evolution
Attempt any five of the following questions.
Q3(4) $What is embryology? How does its study lead us to understand evolution?$
Speciation and Evidences of Evolution

March 2016

4 q

Q1(A)(4) $Considering the relationship in the first pair, complete the second pair: rr : Homozygous : : Rr : ____________$
Heredity and Variation
Q2(2) $What is the peculiarity of the 'DNA' structure?$
Heredity and Variation
Q2(6) $What are fossils?$
Speciation and Evidences of Evolution
Q3(2) $How is sex determined in human beings?$
Heredity and Variation

The 10 board questions to practise first

The questions the board asked again come first, most asked first. Each one says how often and when.

Question 1
Asked 3 times: Mar 2024, Jul 2024, Jul 2025
Q3(iii) $खालील प्रश्नांची उत्तरे लिहा : (अ) अवशेषांग म्हणजे काय ? (आ) मानवी शरीरातील दोन अवशेषांगांची नांवे लिहा. (इ) मानवासाठी निरुपयोगी परंतु इतर प्राण्यांसाठी उपयुक्त व कार्यक्षम असलेल्या दोन अवशेषांगांची नावे लिहा. Answer the following questions: (a) Define vestigial organs. (b) Write names of any two vestigial organs in human body. (c) Write the names of any two vestigial organs which are non-functional in human beings but functional in other organisms.$
Question 2
Asked 3 times: Mar 2016, Mar 2018, Mar 2019* (* = numbers or wording changed that year)
Q4(ii)(a) $'Gender of a child is determined by the male partner of a couple.' Draw a diagram explaining the above statement.$
Question 3
Asked 2 times: Mar 2022, Jun 2026* (* = numbers or wording changed that year)
Q3(i) $खालील आकृती पूर्ण करा : उत्क्रांतीचे पुरावे : शरीरशास्त्रीय पुरावे, ____, ____, ____Complete the following diagram: (Concept map 'Evidences of Evolution' with four boxes: Anatomical, ____________, ____________, ____________.)$
Question 4
Asked 2 times: Mar 2019, Jun 2026* (* = numbers or wording changed that year)
Q2(A)(i) $शास्त्रीय कारणे लिहा : पेरीपॅटस हा ॲनेलिडा व संधिपाद प्राणी या दोघांना जोडणारा दुवा आहे. Give scientific reason: Peripatus is connecting link between Annelida and Arthropoda.$
Question 5
Asked 2 times: Jul 2024, Jul 2025* (* = numbers or wording changed that year)
Q1(B)(i) $चूक की बरोबर ते लिहा : उत्क्रांती म्हणजे सजीवांमध्ये अत्यंत सावकाश होणारा क्रमिक बदल होय. State whether the following statement is True or False: Evolution is the gradual change occurring in living organisms over a long duration.$
Question 6
Asked 2 times: Mar 2024, Mar 2025* (* = numbers or wording changed that year)
Q1(A)(iii) $जनुकांमध्ये अचानक बदल होवून सजीवात लहानसा बदल घडून येतो. तो बदल म्हणजेच ____ होय. Any nucleotide of the gene suddenly changes its position that causes a minor change which is nothing but the ____.$
Tap an option to check your answer.
Question 7
This type asked 7 times: Mar 2016, Mar 2017, Mar 2020, Mar 2025, Jul 2025, Mar 2026, Jun 2026. This one: Jun 2026
Q1(A)(i) $‘देवमाशाचा पर’ हा ____ विषयक पुरावा आहे. Flipper of whale is ____________ type of evidence of evolution.$
Tap an option to check your answer.
Question 8
This type asked 4 times: Mar 2017, Mar 2018, Mar 2023, Mar 2024. This one: Mar 2023
Q1(A)(i) $Vestigial organ ____ present in human body is proof of evolution.$
Tap an option to check your answer.
Question 9
This type asked 4 times: Mar 2016, Mar 2017, Mar 2018, Mar 2024. This one: Mar 2024
Q1(B)(v) $44 + XX$
Question 10
This type asked 3 times: Mar 2022, Mar 2023, Mar 2026. This one: Mar 2026
Q3(i) $लॅमार्कवाद सिद्धांत लिहून तो दोन उदाहरणांद्वारे स्पष्ट करा. Explain the theory of Lamarckism with the help of any two suitable examples.$

Exercise

What the board has asked from this chapter

June 2026

March 2026

July 2025

March 2025

July 2024

March 2024

March 2023

March 2022

March 2020

March 2019

March 2018

March 2017

March 2016

The 10 board questions to practise first

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10