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Chapter 7 Evolution
Multiple Choice Questions
Question 1. Which of the following is used as an atmospheric pollution indicator?
a. Lepidoptera
b. Lichens
c. Lycopersicon
d. Lycopodium
Answer:
Question 2. The theory of spontaneous generation stated that:
a. life arose from living forms only
b. life can arise from both living and non-living
c. life can arise from non-living things only.
d. life arises spontaneously, neither from living nor from the non-living.
Answer:
Question 3. Animal husbandry and plant breeding programmes are the examples of:
a. reverse evolution
b. artificial selection
c. mutation
d. natural selection
Answer:
Question 4. Palaentological evidences for evolution refer to the:
a. development of embryo
b. homologous organs
c. fossils
d. analogous organs.
Answer:
Question 5. The bones of forelimbs of whale, bat, cheetah and man are similar in structure, because:
a. one organism has given rise to another
b. they share a common ancestor
c. they perform the same function
d. the have biochemical similarities
Answer:
Question 6. Analogous organs arise due to:
a. divergent evolution
b. artificial selection
c. genetic drift
d. convergent evolution
Answer:
Question 7. $(p+q)^2 = p^2 + 2pq + q^2 = 1$ represents an equation used in:
a. population genetics
b. mendelian genetics
c. biometrics
d. molecular genetics
Answer:
Question 8. Appearance of antibiotic-resistant bacteria is an example of:
a. adaptive radiation
b. transduction
c. pre-existing variation in the population
d. divergent evolution
Answer:
Question 9. Evolution of life shows that life forms had a trend of moving from:
a. land to water
b. dryland to wet land
c. fresh water to sea water
d. water to land
Answer:
Question 10. Viviparity is considered to be more evolved because:
a. the young ones are left on their own
b. the young ones are protected by a thick shell
c. the young ones are protected inside the mother's body and are looked after they are born leading to more chances of survival
d. the embryo takes a long time to develop
Answer:
Question 11. Fossils are generally found in:
a. Sedimentary rocks
b. Igneous rocks
c. Metamorphic rocks
d. Any type of rock
Answer:
Question 12. For the MN-blood group system, the frequencies of M and N alleles are 0.7 and 0.3, respectively. The expected frequency of MN-blood group bearing organisms is likely to be
a. 42%
b. 49%
c. 9%
d. 58%
Answer:
Question 13. Which type of selection explains industrial melanism observed in moth, Biston bitularia:
a. Stabilising
b. Directional
c. Disruptive
d. Artificial
Answer:
Question 14. The most accepted line of descent in human evolution is:
a. Australopithecus $→$ Ramapithecus $→$ Homo sapiens $→$ Homo habilis
b. Homo erectus $→$ Homo habilis $→$ Homo sapiens
c. Ramapithecus $→$ Homo habilis $→$ Homo erectus $→$ Homo sapiens
d. Australopithecus $→$ Ramapithecus $→$ Homo erectus $→$ Homo habilis $→$ Homo sapiens.
Answer:
Question 15. Which of the following is an example for link species?
a. Lobe fish
b. Dodo bird
c. Sea weed
d. Chimpanzee
Answer:
Question 16. Match the scientists listed under column ‘I’ with ideas listed column ‘II’.
| Column I | Column II |
|---|---|
| A. Darwin | i. abiogenesis |
| B. Oparin | ii. use and disuse of organs |
| C. Lamarck | iii. continental drift theory |
| D. Wagner | iv. evolution by natural selection |
a. A-i; B-iv; C-ii; D-iii
b. A-iv; B-i; C-ii; D-iii
c. A-ii; B-iv; C-iii; D-i
d. A-iv; B-iii; C-ii; D-i
Answer:
Question 17. In 1953 S. L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for origin of first form of life from pre-existing non-living organic molecules. The primitive earth conditions created include:
a. low temperature, volcanic storms, atmosphere rich in oxygen
b. low temperature, volcanic storms, reducing atmosphere
c. high temperature, volcanic storms, non-reducing atmosphere
d. high temperature, volcanic storms, reducing atmosphere containing $CH_4$, $NH_3$ etc.
Answer:
Question 18. Variations during mutations of meiotic recombinations are:
a. random and directionless
b. random and directional
c. small and directional
d. random, small and directional
Answer:
Very Short Answer Questions
Question 1. What were the characteristics of life forms that had been fossilised?
Answer:
Question 2. Did aquatic life forms get fossilised? If, yes where do we come across such fossils?
Answer:
Question 3. What are we referring to? When we say 'simple organisms' or 'complex organisms'.
Answer:
Question 4. How do we compute the age of a living tree?
Answer:
Question 5. Give an example for convergent evolution and identify the features towards which they are converging.
Answer:
Question 6. How do we compute the age of a fossil?
Answer:
Question 7. What is the most important pre-condition for adaptive radiation?
Answer:
Question 8. How do we compute the age of a rock?
Answer:
Question 9. When we talk of functional macromolecules (e.g. proteins as enzymes, hormones, receptors, antibodies etc), towards what are they evolving?
Answer:
Question 10. In a certain population, the frequency of three genotypes is as follows:
| Genotypes: | BB | Bb | bb |
| frequency: | 22% | 62% | 16% |
What is the likely frequency of B and b alleles?
Answer:
Question 11. Among the five factors that are known to affect Hardy-Weinberg equilibrium, three factors are gene flow, genetic drift and genetic recombination. What are the other two factors?
Answer:
Question 12. What is founder effect?
Answer:
Question 13. Who among the Dryopithecus and Ramapithecus was more man-like?
Answer:
Question 14. By what Latin name the first hominid was known?
Answer:
Question 15. Among Ramapithecus, Australopithecines and Homo habilis - who probably did not eat meat?
Answer:
Short Answer Questions
Question 1. Louis Pasteur’s experiments, if you recall, proved that life can arise from only pre-existing life. Can we correct this as life evolves from pre-existent life or otherwise we will never answer the question as to how the first forms of life arose? Comment.
Answer:
Question 2. The scientists believe that evolution is gradual. But extinction, part of evolutionary story, are 'sudden' and 'abrupt' and also group-specific. Comment whether a natural disaster can be the cause for extinction of species.
Answer:
Question 3. Why is nascent oxygen supported to be toxic to aerobic life forms?
Answer:
Question 4. While creation and presence of variation is directionless, natural selection is directional as it is in the context of adaptation. Comment.
Answer:
Question 5. The evolutionary story of moths in England during industrialisation reveals, that 'evolution is apparently reversible'. Clarify this statement.
Answer:
Question 6. Comment on the statement that "evolution and natural selection are end result or consequence of some other processes but themselves are not processes".
Answer:
Question 7. State and explain any three factors affecting allele frequency in populations.
Answer:
Question 8. Gene flow occurs through generations. Gene flow can occur across language barriers in humans. If we have a technique of measuring specific allele frequencies in different population of the world, can we not predict human migratory patterns in pre-history and history? Do you agree or disagree? Provide explanation to your answer.
Answer:
Question 9. How do you express the meaning of words like race, breed, cultivars or variety?
Answer:
Question 10. When we say "survival of the fittest", does it mean that
a. those which are fit only survive, or
b. those that survive are called fit?
Comment.
Answer:
Question 11. Enumerate three most characteristic criteria for designating a Mendelian population.
Answer:
Question 12. "Migration may enhance or blurr the effects of selection". Comment.
Answer:
Long Answer Questions
Question 1. Name the law that states that the sum of allelic frequencies in a population remains constant. What are the five factors that influence these values?
Answer:
Question 2. Explain divergent evolution in detail. What is the driving force behind it?
Answer:
Question 3. You have studied the story of Pepper moths in England. Had the industries been removed, what impact could it have on the moth population? Discuss.
Answer:
Question 4. What are the key concepts in the evolution theory of Darwin?
Answer:
Question 5. Two organisms occupying a particular geographical area (say desert) show similar adaptive strategies. Taking examples, describe the phenomenon.
Answer:
Question 6. We are told that evolution is a continuing phenomenon for all living things. Are humans also evolving? Justify your answer.
Answer:
Question 7. Had Darwin been aware of Mendel’s work, would he been able to explain the origin of variations. Discuss.
Answer: