NCERT NEET Biology English Medium Part-1 | Chapter 25 : Evolution.

NCERT NEET Biology English Medium Part-1 | Chapter 25 : Evolution.

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Question 1. The Big Bang theory explains the origin of the universe through a singular, unimaginable explosion. Which of the following events occurred immediately after this explosion?

1. a) Condensation of gases under gravitation to form galaxies.
2. b) Expansion of the universe leading to a decrease in temperature.
3. c) Immediate formation of water vapour and methane.
4. d) Formation of the ozone layer.

Answer: b.

Question 2. According to the geological history of the Earth, when did life first appear on the planet?

4. a) 4.5 billion years back.
5. b) 20 billion years back.
6. c) 500 million years after the formation of Earth.
7. d) 3 billion years back.

Answer: c.

Question 3. In the context of early Earth, which of the following statements is incorrect based on the PYQ model analysis?

1. a) There was no atmosphere on early Earth.
2. b) UV rays from the sun broke up water into Hydrogen and Oxygen.
3. c) Free oxygen actively reacted with methane to form macromolecules.
4. d) The lighter Hydrogen gas escaped from the surface.

Answer: c.

Question 4. Louis Pasteur's careful experimentation dismissed the theory of spontaneous generation. What did he demonstrate in his experiment?

1. a) Life came from decaying and rotting matter like straw and mud.
2. b) Life comes only from pre-existing life in sterilised flasks.
3. c) First life forms came from non-living organic molecules.
4. d) Spores were transferred from different planets to Earth.

Answer: b.

Question 5. Oparin and Haldane proposed that the first form of life could have come from pre-existing non-living organic molecules. Which of the following best describes this process?

1. a) Biological evolution.
2. b) Chemical evolution.
3. c) Spontaneous generation.
4. d) Panspermia.

Answer: b.

Question 6. S.L. Miller created conditions similar to primitive Earth in a laboratory scale. Which of the following gas mixtures was used in his closed flask experiment at 800 degree Celsius?

1. a) Methane, Hydrogen, Ammonia, and water vapour.
2. b) Methane, Oxygen, Ammonia, and water vapour.
3. c) Carbon dioxide, Nitrogen, Oxygen, and water vapour.
4. d) Ammonia, Methane, Carbon dioxide, and Hydrogen.

Answer: a.

Question 7. What was the major organic compound observed to be formed in S.L. Miller's experiment?

1. a) Nucleic acids.
2. b) Amino acids.
3. c) Polysaccharides.
4. d) Complex lipids.

Answer: b.

Question 8. The first non-cellular forms of life are estimated to have originated 3 billion years back. What were they most likely composed of?

1. a) Single-celled prokaryotes with cell walls.
2. b) Giant molecules like RNA, Proteins, and Polysaccharides.
3. c) Simple eukaryotic cells with mitochondria.
4. d) Coacervates with active DNA replication.

Answer: b.

Question 9. Statement I: The first cellular form of life did not possibly originate till about 2000 million years ago. Statement II: All these initial life forms evolved strictly in a terrestrial environment. Choose the correct option.

1. a) Both Statement I and Statement II are correct.
2. b) Both Statement I and Statement II are incorrect.
3. c) Statement I is correct but Statement II is incorrect.
4. d) Statement I is incorrect but Statement II is correct.

Answer: c.

Question 10. Charles Darwin concluded that existing living forms share similarities to varying degrees. Which ship did he use for his sea voyage around the world?

1. a) H.M.S. Challenger.
2. b) H.M.S. Beagle.
3. c) H.M.S. Victoria.
4. d) H.M.S. Discovery.

Answer: b.

Question 11. According to Darwin, what is the ultimate measure of fitness in an environment?

1. a) Physical strength.
2. b) Maximum lifespan.
3. c) Reproductive fitness.
4. d) Ability to migrate.

Answer: c.

Question 12. Alfred Wallace, a naturalist who came to conclusions similar to Darwin around the same time, worked in which geographical region?

1. a) Galapagos Islands.
2. b) Malay Archipelago.
3. c) Australian continent.
4. d) Madagascar.

Answer: b.

 

Question 13. Which of the following provides paleontological evidence for evolution?

1. a) Vestigial organs in modern mammals.
2. b) Biochemical similarities in proteins.
3. c) Fossils found in different sedimentary rock layers.
4. d) Similar early embryonic development in vertebrates.

Answer: c.

 

Question 14. Ernst Haeckel proposed embryological support for evolution. Who carefully studied and disapproved this proposal by noting that embryos never pass through the adult stages of other animals?

1. a) Karl Ernst von Baer.
2. b) Charles Darwin.
3. c) Hugo de Vries.
4. d) Thomas Malthus.

Answer: a.

Question 15. The forelimbs of whales, bats, cheetahs, and humans share similarities in the pattern of bones. What type of evolution does this represent?

1. a) Convergent evolution.
2. b) Divergent evolution.
3. c) Parallel evolution.
4. d) Reverse evolution.

Answer: b.

Question 16. Which of the following is not included in the similar anatomical structure of the forelimbs of mammals demonstrating homology?

1. a) Humerus and radius.
2. b) Ulna and carpals.
3. c) Metacarpals and phalanges.
4. d) Femur and tibia.

Answer: d.

Question 17. The thorn of Bougainvillea and tendrils of Cucurbita represent which evolutionary phenomenon?

1. a) Analogy.
2. b) Homology.
3. c) Adaptive radiation.
4. d) Convergent evolution.

Answer: b.

Question 18. Assertion (A): Wings of a butterfly and of birds are analogous structures. Reason (R): Analogous structures are a result of convergent evolution, where different structures evolve for the same function.

1. a) Both A and R are true and R is the correct explanation of A.
2. b) Both A and R are true but R is not the correct explanation of A.
3. c) A is true but R is false.
4. d) A is false but R is true.

Answer: a.

Question 19. Sweet potato and potato represent an example of analogy. Which parts of the plants are modified in these two cases, respectively?

1. a) Stem modification and root modification.
2. b) Root modification and stem modification.
3. c) Leaf modification and stem modification.
4. d) Root modification and leaf modification.

Answer: b.

Question 20. The eye of the octopus and the eye of mammals are examples of which type of evolutionary relationship?

1. a) Homology.
2. b) Analogy.
3. c) Atavism.
4. d) Vestigial structures.

Answer: b.

Question 21. Biochemical similarities in proteins and genes performing a given function among diverse organisms give clues to what evolutionary concept?

1. a) Convergent evolution.
2. b) Shared common ancestry.
3. c) Industrial melanism.
4. d) Genetic drift.

Answer: b.

Question 22. In the 1850s, before industrialisation set in England, there were more white-winged moths on trees than dark-winged moths. What was the primary reason for this?

1. a) Dark-winged moths were genetically defective and died early.
2. b) White-winged moths camouflaged well against the white lichen-covered tree trunks.
3. c) Predators preferred the taste of white-winged moths but could not catch them.
4. d) Industrial smoke killed the dark-winged moths selectively.

Answer: b.

Question 23. After industrialisation in 1920, the proportion of moth populations in England reversed. Which biological process is strongly supported by this observation?

1. a) Artificial selection.
2. b) Mutation theory.
3. c) Evolution by natural selection.
4. d) Inheritance of acquired characters.

Answer: c.

Question 24. Which organism is commonly known as an industrial pollution indicator because it does not grow in polluted areas?

1. a) Cyanobacteria.
2. b) Mycorrhizae.
3. c) Lichens.
4. d) Methanogens.

Answer: c.

Question 25. The evolution of different species in a given geographical area starting from a point and literally spreading to other areas of geography is called what?

1. a) Convergent evolution.
2. b) Adaptive radiation.
3. c) Genetic drift.
4. d) Saltation.

Answer: b.

Question 26. Which of the following is a classic example of adaptive radiation studied by Charles Darwin?

1. a) Industrial melanism in moths.
2. b) Resistance of bacteria to antibiotics.
3. c) Darwin's finches of the Galapagos Islands.
4. d) Development of breeds in dogs.

Answer: c.

Question 27. Australian marsupials evolved from an ancestral stock within the Australian island continent. This process is an example of which evolutionary mechanism?

1. a) Adaptive radiation.
2. b) Artificial selection.
3. c) Convergent evolution.
4. d) Anthropogenic evolution.

Answer: a.

Question 28. When more than one adaptive radiation appears to have occurred in an isolated geographical area representing different habitats, what is it referred to as?

1. a) Divergent evolution.
2. b) Convergent evolution.
3. c) Parallel radiation.
4. d) Disruptive selection.

Answer: b.

Question 29. Match the placental mammal with its corresponding convergent Australian marsupial. Placental Wolf corresponds to which Marsupial?

1. a) Marsupial mole.
2. b) Spotted cuscus.
3. c) Tasmanian wolf.
4. d) Numbat.

Answer: c.

Question 30. Which placental mammal shows convergent evolution with the Australian marsupial called the Numbat (anteater)?

1. a) Lemur.
2. b) Bobcat.
3. c) Anteater.
4. d) Flying squirrel.

Answer: c.

Question 31. The essence of Darwinian theory about evolution is natural selection. What are the two key concepts of Darwinian Theory of Evolution?

1. a) Branching descent and natural selection.
2. b) Mutation and genetic drift.
3. c) Use and disuse of organs and inheritance.
4. d) Saltation and founder effect.

Answer: a.

Question 32. Who proposed the theory of evolution driven by the use and disuse of organs, using the elongation of the giraffe's neck as an example?

1. a) Charles Darwin.
2. b) Alfred Wallace.
3. c) Jean Baptiste Lamarck.
4. d) Hugo de Vries.

Answer: c.

Question 33. Thomas Malthus greatly influenced Darwin. What was the central theme of Malthus's work?

1. a) Principles of Geology.
2. b) Essays on populations and resources.
3. c) Inheritance of acquired characteristics.
4. d) Mutation theory in plants.

Answer: b.

Question 34. In the first decade of the twentieth century, who brought forth the idea of mutations based on his work on evening primrose?

1. a) Gregor Mendel.
2. b) Thomas Hunt Morgan.
3. c) Hugo de Vries.
4. d) Hardy and Weinberg.

Answer: c.

Question 35. According to Hugo de Vries, what causes speciation?

1. a) Small directional variations.
2. b) Continuous geographical isolation.
3. c) Single step large mutation.
4. d) Gradual natural selection.

Answer: c.

Question 36. Statement I: Darwinian variations are small and directional. Statement II: Mutations according to de Vries are random and directionless. Choose the correct option.

1. a) Both Statement I and Statement II are true.
2. b) Both Statement I and Statement II are false.
3. c) Statement I is true but Statement II is false.
4. d) Statement I is false but Statement II is true.

Answer: a.

Question 37. What term did Hugo de Vries use to describe the mechanism of evolution through a single step large mutation?

1. a) Genetic drift.
2. b) Saltation.
3. c) Recombination.
4. d) Gene flow.

Answer: b.

Question 38. The Hardy-Weinberg principle states that allele frequencies in a population are stable and constant from generation to generation. What is this state of stability called?

1. a) Evolutionary stasis.
2. b) Genetic equilibrium.
3. c) Directional selection.
4. d) Reproductive isolation.

Answer: b.

Question 39. In the Hardy-Weinberg algebraic equation (p^2 + 2pq + q^2 = 1), what does 2pq represent in a diploid population?

1. a) Frequency of homozygous dominant individuals.
2. b) Frequency of heterozygous individuals.
3. c) Frequency of homozygous recessive individuals.
4. d) Sum total of all allelic frequencies.

Answer: b.

Question 40. According to the Hardy-Weinberg principle, the sum total of all the allelic frequencies in a given population is equal to what value?

1. a) Zero.
2. b) One.
3. c) Infinity.
4. d) One hundred.

Answer: b.

Question 41. Which of the following is not one of the five factors known to affect Hardy-Weinberg equilibrium?

1. a) Gene migration.
2. b) Genetic drift.
3. c) Random mating.
4. d) Natural selection.

Answer: c.

Question 42. When gene migration happens multiple times between populations, it causes a change in gene frequencies. What is this phenomenon specifically called?

1. a) Genetic load.
2. b) Gene flow.
3. c) Genetic drift.
4. d) Saltation.

Answer: b.

Question 43. If a change in gene frequency occurs entirely by chance in a small population, what is the evolutionary mechanism at work?

1. a) Natural selection.
2. b) Mutation.
3. c) Genetic drift.
4. d) Disruptive selection.

Answer: c.

Question 44. Sometimes the change in allele frequency is so different in the new sample of a population that they become a different species. What is the original drifted population called in this context?

1. a) Founder.
2. b) Mutant.
3. c) Pioneer.
4. d) Ancestor.

Answer: a.

Question 45. In natural selection, if more individuals acquire the mean character value, leading to a narrower and higher peak on the distribution curve, which type of selection is operating?

1. a) Directional selection.
2. b) Disruptive selection.
3. c) Stabilising selection.
4. d) Artificial selection.

Answer: c.

Question 46. If natural selection leads to more individuals acquiring values other than the mean character value, and the peak shifts in one direction, what type of selection is this?

1. a) Stabilising selection.
2. b) Directional selection.
3. c) Disruptive selection.
4. d) Balancing selection.

Answer: b.

Question 47. When natural selection results in more individuals acquiring peripheral character values at both ends of the distribution curve, forming two peaks, what is it termed?

1. a) Stabilising selection.
2. b) Directional selection.
3. c) Disruptive selection.
4. d) Founder effect.

Answer: c.

Question 48. Approximately when did the first cellular forms of life appear on Earth?

1. a) 3 billion years ago.
2. b) 2000 million years ago.
3. c) 500 million years ago.
4. d) 4.5 billion years ago.

Answer: b.

Question 49. Based on the geological time scale, when were invertebrates formed and active?

1. a) 500 mya.
2. b) 350 mya.
3. c) 320 mya.
4. d) 200 mya.

Answer: a.

Question 50. Jawless fish probably evolved around which period in Earth's history?

1. a) 500 mya.
2. b) 350 mya.
3. c) 320 mya.
4. d) 65 mya.

Answer: b.

Question 51. Which organisms were the first to successfully invade land according to evolutionary records?

1. a) Amphibians.
2. b) Reptiles.
3. c) Plants.
4. d) Insects.

Answer: c.

Question 52. In 1938, a fish caught in South Africa happened to be a Coelacanth. Why was this discovery highly significant for evolutionary biology?

1. a) It was the first fish to show lungs for breathing air directly.
2. b) It was thought to be extinct and belongs to lobefins that evolved into the first amphibians.
3. c) It was the missing link between amphibians and reptiles.
4. d) It possessed a cartilaginous skeleton identical to modern sharks.

Answer: b.

Question 53. The lobefins evolved into early amphibians that lived both on land and in water. Which modern animals are the descendants of these early amphibians?

1. a) Snakes and lizards.
2. b) Frogs and salamanders.
3. c) Crocodiles and turtles.
4. d) Fish and rays.

Answer: b.

Question 54. Amphibians evolved into reptiles. Which key reproductive adaptation allowed reptiles to avoid going back to water to reproduce?

1. a) Internal fertilisation.
2. b) Viviparity.
3. c) Laying thick-shelled eggs which do not dry up in sun.
4. d) Metamorphosis through a larval stage.

Answer: c.

Question 55. During which period did giant ferns (pteridophytes) predominantly exist before falling to form massive coal deposits?

1. a) Triassic.
2. b) Carboniferous.
3. c) Jurassic.
4. d) Cretaceous.

Answer: b.

Question 56. Around 200 million years ago, some land reptiles went back into water to evolve into fish-like reptiles. What were these reptiles called?

1. a) Pteranodons.
2. b) Tyrannosaurus.
3. c) Ichthyosaurs.
4. d) Plesiosaurs.

Answer: c.

Question 57. Which was the biggest dinosaur, measuring about 20 feet in height with huge fearsome dagger-like teeth?

1. a) Triceratops.
2. b) Stegosaurus.
3. c) Brachiosaurus.
4. d) Tyrannosaurus rex.

Answer: d.

Question 58. Approximately when did the dinosaurs suddenly disappear from the face of the Earth?

1. a) 200 million years ago.
2. b) 150 million years ago.
3. c) 65 million years ago.
4. d) 10 million years ago.

Answer: c.

Question 59. The first true mammals to appear in evolutionary history were small and had fossil records indicating they resembled which modern animal?

1. a) Shrews.
2. b) Monkeys.
3. c) Rabbits.
4. d) Bats.

Answer: a.

Question 60. Mammals became successful and took over the Earth after the decline of dinosaurs. Which of the following is not a characteristic feature of early mammals that aided their survival?

1. a) They were viviparous and protected their unborn young inside the mother's body.
2. b) They were intelligent in sensing and avoiding danger.
3. c) They laid amniotic eggs in safe nests on land.
4. d) They maintained a constant body temperature.

Answer: c.

Question 61. South America initially possessed distinct mammalian fauna like horse, hippopotamus, and bear-like animals. What caused these animals to be overridden by North American fauna?

1. a) Climatic changes leading to ice ages.
2. b) Continental drift joining South America with North America.
3. c) An asteroid impact near the region.
4. d) Mass viral epidemics.

Answer: b.

Question 62. Why did Australian marsupials survive and diversify despite lacking the complex placental reproduction seen in other mammals?

1. a) They evolved faster reproductive cycles than placental mammals.
2. b) Continental drift isolated them from competition with placental mammals.
3. c) They adapted to an exclusively carnivorous diet.
4. d) They developed superior intelligence and tool use.

Answer: b.

Question 63. About 15 million years ago, primates called Dryopithecus and Ramapithecus existed. Which of the following accurately describes their physical characteristics?

1. a) Hairless, upright posture, and tool use.
2. b) Hairy and walked like gorillas and chimpanzees.
3. c) Large brain capacity with advanced bipedalism.
4. d) Tail-bearing quadrupeds with prehensile hands.

Answer: b.

Question 64. Between Ramapithecus and Dryopithecus, which primate was considered more man-like?

1. a) Dryopithecus.
2. b) Ramapithecus.
3. c) Both were equally man-like.
4. d) Neither showed any man-like traits.

Answer: b.

Question 65. Fossils discovered in Ethiopia and Tanzania revealed hominid features leading to the belief that man-like primates walked in eastern Africa. When did this occur?

1. a) 15 million years ago.
2. b) 3-4 million years ago.
3. c) 1.5 million years ago.
4. d) 100,000 years ago.

Answer: b.

Question 66. Australopithecines lived in East African grasslands about 2 million years ago. Based on available evidence, what was their primary diet?

1. a) Cooked meat.
2. b) Raw meat hunted with stone weapons.
3. c) Essentially fruits.
4. d) Fish and aquatic plants.

Answer: c.

Question 67. Which of the following is considered the first human-like being, also referred to as the hominid?

1. a) Australopithecus.
2. b) Homo habilis.
3. c) Homo erectus.
4. d) Homo sapiens.

Answer: b.

Question 68. What was the approximate brain capacity of Homo habilis?

1. a) 400-500 cc.
2. b) 650-800 cc.
3. c) 900 cc.
4. d) 1400 cc.

Answer: b.

Question 69. Fossils discovered in Java in 1891 revealed the next stage of human evolution, which existed about 1.5 million years ago. Identify the species.

1. a) Homo habilis.
2. b) Australopithecus africanus.
3. c) Homo erectus.
4. d) Neanderthal man.

Answer: c.

Question 70. Homo erectus showed a significant increase in cranial capacity compared to its predecessors. What was its approximate brain size?

1. a) 650 cc.
2. b) 800 cc.
3. c) 900 cc.
4. d) 1400 cc.

Answer: c.

Question 71. Based on fossil and archeological evidence, Homo erectus is believed to have consumed what type of diet?

1. a) Exclusively herbivorous.
2. b) Probably ate meat.
3. c) Strictly frugivorous.
4. d) Consumed only cooked agricultural grains.

Answer: b.

Question 72. Which hominid species lived near East and Central Asia between 100,000 to 40,000 years back and possessed a brain size of 1400 cc?

1. a) Homo habilis.
2. b) Homo erectus.
3. c) Neanderthal man.
4. d) Australopithecus.

Answer: c.

Question 73. Which of the following cultural practices is closely associated with Neanderthal man?

1. a) Invention of the wheel.
2. b) Cultivating crops and domesticating animals.
3. c) Using hides to protect their body and burying their dead.
4. d) Creating pre-historic cave art.

Answer: c.

Question 74. Modern Homo sapiens arose during the ice age. In what timeframe did this development occur?

1. a) 1,000,000 - 500,000 years ago.
2. b) 100,000 - 40,000 years ago.
3. c) 75,000 - 10,000 years ago.
4. d) 18,000 - 5,000 years ago.

Answer: c.

Question 75. Pre-historic cave art provides significant insight into human cultural evolution. Approximately when did such cave art develop?

1. a) 75,000 years ago.
2. b) 40,000 years ago.
3. c) 18,000 years ago.
4. d) 10,000 years ago.

Answer: c.

Question 76. Where can one observe famous pre-historic cave paintings created by early humans in India?

1. a) Ajanta Caves in Maharashtra.
2. b) Ellora Caves in Maharashtra.
3. c) Bhimbetka rock shelter in Raisen district of Madhya Pradesh.
4. d) Elephanta Caves near Mumbai.

Answer: c.

Question 77. The shift towards agriculture marked a major turning point in human settlements and the growth of civilisations. When did agriculture begin?

1. a) 100,000 years back.
2. b) 40,000 years back.
3. c) 18,000 years back.
4. d) 10,000 years back.

Answer: d.

Question 78. When comparing the skulls of humans and chimpanzees, which of the following statements is true based on evolutionary morphological studies?

1. a) The adult chimpanzee skull is completely identical to the adult human skull.
2. b) The skull of a baby chimpanzee is more like the adult human skull than the adult chimpanzee skull.
3. c) The baby human skull resembles the adult chimpanzee skull more than the adult human skull.
4. d) There are no measurable morphological similarities between human and chimpanzee skulls.

Answer: b.

Question 79. Assertion (A): Evolution is considered a stochastic process. Reason (R): It is based on chance events in nature and chance mutations in the organisms.

1. a) Both A and R are true and R is the correct explanation of A.
2. b) Both A and R are true but R is not the correct explanation of A.
3. c) A is true but R is false.
4. d) A is false but R is true.

Answer: a.

Question 80. The development of antibiotic-resistant bacteria is frequently cited as a modern example of evolution. This specifically illustrates which concept?

1. a) Evolution by anthropogenic action.
2. b) Adaptive radiation in natural untouched habitats.
3. c) Convergent evolution of biochemical pathways.
4. d) Spontaneous generation of resistance genes.

Answer: a.

Question 81. In the context of plant evolution, which group directly gave rise to the Bryophytes?

1. a) Chlorophyte ancestors.
2. b) Tracheophyte ancestors.
3. c) Rhynia-type plants.
4. d) Psilophyton.

Answer: a.

Question 82. Which ancestral plant group represents the common evolutionary precursor to both Dicotyledons and Monocotyledons?

1. a) Zosterophyllum.
2. b) Seed ferns.
3. c) Progymnosperms.
4. d) Psilophyton.

Answer: b.

Question 83. The evolutionary line of plants that led to ferns, conifers, and flowering plants passed through which significant ancestral form?

1. a) Chlorophyte ancestors.
2. b) Bryophytes.
3. c) Psilophyton.
4. d) Zosterophyllum.

Answer: c.

Question 84. Match the evolutionary timeframe to the correct organism. 320 mya is associated with the origin of which of the following?

1. a) First cellular forms of life.
2. b) Jawless fish.
3. c) Sea weeds and few plants.
4. d) Invertebrates.

Answer: c.

Question 85. Who heavily debated and challenged the three connotations of the theory of special creation during the nineteenth century?

1. a) Louis Pasteur.
2. b) Oparin and Haldane.
3. c) Charles Darwin.
4. d) S.L. Miller.

Answer: c.

Question 86. Statement I: Homology indicates common ancestry and is based on divergent evolution. Statement II: Analogy indicates similar habitats selecting for similar adaptive features and is based on convergent evolution. Choose the correct option.

1. a) Both Statement I and Statement II are correct.
2. b) Both Statement I and Statement II are incorrect.
3. c) Statement I is correct but Statement II is incorrect.
4. d) Statement I is incorrect but Statement II is correct.

Answer: a.

Question 87. The flippers of Penguins and Dolphins perform similar functions in aquatic environments but have different anatomical origins. They are an example of:

1. a) Divergent evolution.
2. b) Adaptive radiation.
3. c) Homologous structures.
4. d) Analogous structures.

Answer: d.

Question 88. When analyzing PyQ trends for NEET, questions on the Hardy-Weinberg equilibrium often involve calculating the frequency of heterozygotes. If the frequency of a recessive allele 'q' is 0.4, what is the frequency of heterozygotes in the population?

1. a) 0.16.
2. b) 0.36.
3. c) 0.48.
4. d) 0.84.

Answer: c.

Question 89. According to Darwin's theory of natural selection, variation is crucial. What did Darwin consider to be the nature of these variations?

1. a) Large and sudden.
2. b) Small and directional.
3. c) Random and directionless.
4. d) Acquired during an organism's lifetime.

Answer: b.

 

Question 90. Which evolutionary phenomenon is best illustrated by the fact that multiple, distinctly different species of finches inhabit the Galapagos Islands, all originating from a single seed-eating ancestor?

1. a) Artificial selection.
2. b) Convergent evolution.
3. c) Adaptive radiation.
4. d) Punctuated equilibrium.

Answer: c.

Question 91. The mutation theory proposed by Hugo de Vries challenged Darwinian evolution on which specific point?

1. a) The importance of reproductive fitness.
2. b) The concept of common ancestry.
3. c) The gradual and continuous nature of evolutionary changes.
4. d) The existence of fossils in sedimentary rocks.

Answer: c.

Question 92. Identify the incorrect statement regarding human evolution from the options below.

1. a) Homo habilis had a cranial capacity of 650-800 cc and did not eat meat.
2. b) Homo erectus appeared about 1.5 million years ago and had a cranial capacity of 900 cc.
3. c) Neanderthal man had a smaller cranial capacity than Homo erectus and lacked cultural practices.
4. d) Homo sapiens arose in Africa and moved across continents.

Answer: c.

Question 93. In the sequence of human evolution, which species is chronologically placed immediately before Homo sapiens?

1. a) Homo habilis.
2. b) Australopithecus.
3. c) Ramapithecus.
4. d) Neanderthal man.

Answer: d.

Question 94. The concept of 'genetic drift' is most accurately applicable to which type of populations?

1. a) Infinitely large and randomly mating populations.
2. b) Small and isolated populations.
3. c) Populations with high mutation rates.
4. d) Populations undergoing strong natural selection.

Answer: b.

Question 95. What was the primary driving force that allowed early reptiles to dominate terrestrial environments over amphibians?

1. a) Development of a highly complex brain.
2. b) The evolution of the amniotic egg with a thick shell.
3. c) Transition to a strictly herbivorous diet.
4. d) The ability to undergo metamorphosis.

Answer: b.

Question 96. Which scientist's observations in the Malay Archipelago provided independent support for the mechanism of natural selection concurrently with Darwin?

1. a) Thomas Malthus.
2. b) Charles Lyell.
3. c) Alfred Wallace.
4. d) Jean-Baptiste Lamarck.

Answer: c.

Question 97. If a population undergoes disruptive selection, what long-term evolutionary outcome is most likely to occur?

1. a) The population becomes genetically uniform.
2. b) Speciation into two distinct lineages.
3. c) Extinction of the extreme variants.
4. d) Return to the original mean phenotype.

Answer: b.

Question 98. From an evolutionary perspective, the retention of vestigial organs in modern organisms serves as evidence for:

1. a) Special creation.
2. b) Saltation.
3. c) Descent with modification from common ancestors.
4. d) Continuous spontaneous generation.

Answer: c.

Question 99. The study of comparative anatomy and morphology demonstrates homology in the vertebrate heart and brain. What underlying evolutionary mechanism produces homologous structures?

1. a) Convergent evolution.
2. b) Divergent evolution.
3. c) Stabilising selection.
4. d) Anthropogenic selection.

Answer: b.

Question 100. Based on the NCERT summary, which event represents the most successful story in the evolution of life forms?

1. a) The transition of lobefins to amphibians.
2. b) The survival of marsupials in Australia.
3. c) The evolution of man with language skills and self-consciousness.
4. d) The adaptive radiation of Darwin's finches.

Answer: c.

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