Evolution Class 12 NEET MCQs - Multiple Choice Questions

1. Alternative forms of a gene are called ______

a) loci

b) multiples

c) Chromosomes

d) Alleles

Answer:

d) Alleles

Explanation:

Explanation: Alleles are alternative forms of a gene that are found at the same place on a chromosome.

2. Heredity or inheritance of specific traits became clearer due to

a) Lamarck’s theory

b) Mendel worked on garden peas

c) Darwinism

d) Neo-Darwinism

Answer:

b) Mendel worked on garden peas

Explanation:

Explanation: Mendel’s experiments with garden peas laid the foundation for understanding the principles of heredity and inheritance of traits.

3. Which of the following sentences is true about the evolutionary process?

a) There is no real ‘progress’ in the idea of evolution.

b) Humans are unique, a totally new type of organism.

c) Progress is nature’s religion.

d) Evolution of life forms was rapid in the beginning ages.

Answer:

a) There is no real ‘progress’ in the idea of evolution.

Explanation:

Explanation: Evolution is not a process of progress towards a goal, but a process of adaptation to changing environmental conditions.

4. Microevolution takes place due to

a) somatogenic variation

b) blastogenic variation

c) continuous variation

d) Successive variation

Answer:

c) continuous variation

Explanation:

Explanation: Microevolution refers to small-scale changes in allele frequencies within a population, often driven by continuous variations in traits.

5. The difference between Homo sapiens and Homo erectus was ______

a) Homo sapiens originated in Africa while Homo erectus was in Asia

b) Homo erectus were much smaller in size than Homo sapiens.

c) Homo erectus stayed in Africa while Homo sapiens did not.

d) The size of their brain of Homo erectus was smaller than that of Homo sapiens

Answer:

d) The size of their brain of Homo erectus was smaller than that of Homo sapiens

Explanation:

Explanation: One of the major differences between Homo sapiens and Homo erectus is the size of the brain, with Homo sapiens having a larger brain size compared to Homo erectus.

6. By studying analogous structures we look for ______

a) similarities in appearance and function but different in structure.

b) similarities in appearance but differences in functions.

c) Similarities in organ structure.

d) Similarities in cell makeup.

Answer:

a) similarities in appearance and function but different in structure.

Explanation:

Explanation: Analogous structures have similar function and appearance but are different in structure and evolutionary origin, demonstrating how different species have evolved separately to adapt to similar environments or challenges.

7. __________ was a predecessor of Darwin and he developed the theory of acquired characteristics.

a) Weismann

b) Mendel

c) Malthus

d) Lamarck

Answer:

d) Lamarck

Explanation:

Explanation: Jean-Baptiste Lamarck proposed the theory of acquired characteristics, suggesting that organisms could change during their lifetimes in response to their environment and pass on those changes to their offspring.

8. Which of these is not a living fossil?

a) Archaeopteryx

b) Duck-billed platypus

c) Lungfish

d) Frog

Answer:

d) Frog

Explanation:

Explanation: A living fossil is an organism that has remained morphologically unchanged for a long period of time. Frogs, while ancient, have diversified into numerous species with various adaptations, unlike the other examples listed which have remained relatively unchanged.

9. Which of the following are not the examples of analogous structures?

a) Wings of bat and butterfly.

b) Wings of bat and forelimb of cattle.

c) Thorn and spine.

d) Tendril of Lathyrus and tendril of Gloriossa.

Answer:

b) Wings of bat and forelimb of cattle.

Explanation:

Explanation: Analogous structures are those that perform a similar function but have different evolutionary origins. The wings of a bat and the forelimb of cattle are not analogous but homologous structures as they share a common evolutionary origin but have different functions.

10. The scientist who cut off the tails of mice of successive generations to prove Lamarck’s theory was wrong was _____.

a) Weismann

b) Haeckel

c) Darwin

d) Wallace

Answer:

a) Weismann

Explanation:

Explanation: August Weismann conducted experiments by cutting off the tails of mice over several generations to disprove Lamarck’s theory of acquired characteristics, showing that such acquired traits were not inherited by subsequent generations.

11. Links between organisms that show branching pattern of evolutionary relationships are shown by_____.

a) living fossils

b) comparative embryology

c) phylogenetic trees

d) two fossil layers

Answer:

c) phylogenetic trees

Explanation:

Explanation: Phylogenetic trees are diagrams that depict the evolutionary relationships among various species based on similarities and differences in their genetic characteristics.

12. Speciation is the evolutionary process by which ______

a) a new gene pool is formed

b) evolutionary paths of species converge

c) hybrid species formed

d) Shows up differences in physical traits

Answer:

a) a new gene pool is formed

Explanation:

Explanation: Speciation is the process by which populations evolve to become distinct species. This occurs mainly due to the genetic isolation from, and subsequent evolution independently of, other populations, leading to a new gene pool.

13. Evidences of evolutionary relationships are found in ______

a) atmosphere

b) fossils

c) ocean beds

d) rocks

Answer:

b) fossils

Explanation:

Explanation: Fossils provide key evidence for understanding the evolutionary history of life on Earth. They help in understanding how modern species have evolved over long periods of time.

14. Which of the following examples of variation is not important from an evolutionary standpoint?

a) Genetic differences between individual organisms comprising the population.

b) Inherited differences between individual organisms comprising the population.

c) Differences due to diet, health, age or accident that have no affect on an individual’s ability to survive and reproduce.

d) a and b.

Answer:

c) Differences due to diet, health, age or accident that have no affect on an individual’s ability to survive and reproduce.

Explanation:

Explanation: From an evolutionary standpoint, genetic and inherited variations are significant as they contribute to the genetic diversity within a population which is crucial for evolution. Variations due to environmental factors like diet, health, age or accident, which are not heritable, do not contribute to evolution.

15. Why is genetic variation important from an evolutionary standpoint?

a) If all organisms were the same, the entire population would be vulnerable to particular pathogens, like viruses.

b) All evolutionary adaptations (e.g. the origin of forelimbs) are the result of the gradual build up of genetic differences between organisms over geologic time.

c) Evolution (at the population level) refers to changes in the frequencies of genes in the population over time.

d) All of the above.

Answer:

d) All of the above.

Explanation:

Explanation: Genetic variation is the foundation for evolutionary changes. It provides the raw material for evolution, enabling populations to adapt to changing environments and also evolve into new species over time.

16. Which of the following is an example of genetic variation?

a) Two children have different eye colors.

b) One person is older than another.

c) One person has a scar, but her friend does not.

d) Tod eats meat, but his brother Rod is a vegetarian.

Answer:

a) Two children have different eye colors.

Explanation:

Explanation: Genetic variation refers to the differences in genes or other DNA segments among individuals within a population. The eye color difference between two children is a classic example of genetic variation.

17. What’s the difference between genetic drift and change due to natural selection?

a) Genetic drift does not require the presence of variation.

b) Genetic drift does not involve competition between members of a species.

c) Genetic drift never occurs in nature, natural selection does.

d) There is no difference.

Answer:

b) Genetic drift does not involve competition between members of a species.

Explanation:

Explanation: Genetic drift is a random change in allele frequencies due to chance events, whereas natural selection is a non-random process where alleles that confer a survival or reproductive advantage are more likely to be passed on to the next generation.

18. According to our reading, how did George Cuvier account for extinctions in nature?

a) Extinctions never occur–there are unexplored parts of the globe where organisms that appear to have gone extinct may still live.

b) Extinctions occur when the slow adaptation of organisms over time to their environment is not quick enough to help them respond to changing conditions.

c) Extinctions occur at random, they do not reflect God’s will.

d) Extinctions are due to catastrophic events.

Answer:

d) Extinctions are due to catastrophic events.

Explanation:

Explanation: George Cuvier was a proponent of the theory of catastrophism, which suggests that Earth’s geology and biodiversity were shaped by sudden, short-lived, violent events, possibly worldwide in scope.

19. Why, according to our reading, did Darwin take so long to publish the Origin of Species?

a) Darwin wanted to share his theory as quickly as possible once he returned from his voyage on the Beagle.

b) It took twenty years for Darwin to develop a theory.

c) Darwin suffered from a number of illnesses.

d) Darwin was concerned about the reaction of others to the implications of his theory.

Answer:

d) Darwin was concerned about the reaction of others to the implications of his theory.

Explanation:

Explanation: Darwin delayed the publication of his theory due to concerns about the reception it would receive from the scientific community and the public, as his theory challenged the prevailing views of the time.

20. In which of the following ways is natural selection not analogous to artificial selection?

a) With natural selection “picking” is due to the fit of an organism with its environment; whereas in artificial selection, the breeder “picks” which organisms will breed.

b) Natural selection depends upon the presence of variation, artificial selection does not.

c) Natural selection occurs within populations, artificial selection does not.

d) There is a limit to how much change can be brought about by natural selection, no such limit exists for artificial selection.

Answer:

d) There is a limit to how much change can be brought about by natural selection, no such limit exists for artificial selection.

Explanation:

Explanation: Natural selection is constrained by factors such as the availability of genetic variation and environmental conditions, whereas artificial selection, directed by humans, can overcome some of these constraints to achieve desired traits in populations.

21. The variation natural selection operates on is due to random mutations. What does this imply about natural selection?

a) Natural selection is also a random process.

b) Natural selection is nevertheless a directed process- the likelihood one variant will be favored in a given environment over another is predictable, even if the origin is not.

c) There is no possibility God could be involved in this process.

d) A, B and C.

Answer:

b) Natural selection is nevertheless a directed process- the likelihood one variant will be favored in a given environment over another is predictable, even if the origin is not.

Explanation:

Explanation: Although mutations occur randomly, natural selection operates on this variation in a non-random manner. Organisms with traits that provide an advantage in a particular environment are more likely to survive and reproduce.

22. How was Mendel’s work ultimately reconciled with Darwin’s theory of natural selection during the evolutionary synthesis in the 1930s and 1940s?

a) Scientists recognized that once one thinks about species as populations, rather than individuals, there is no incompatibility between them.

b) Mendel’s theory was replaced by the mutation theory.

c) It was recognized much of the variation we observe in nature is due to recombination, rather than mutation.

d) A and C.

Answer:

d) A and C.

Explanation:

Explanation: The modern synthesis reconciled Mendelian genetics and Darwinian evolution into a unified theory of evolution. It recognized that both mutation and recombination create genetic variation on which natural selection can act.

23. Which of the following is the evidence for Darwin’s theory of common descent?

a) There are patterns in the fossil record that suggest other species have diverged from a single ancestor species.

b) There are biogeographic patterns in the distribution of species, for instance distinct bird species on an island tend to resemble one another, suggesting a common ancestor.

c) There are common stages in the early embryological development of organisms representing several distinct vertebrate groups.

d) All of the above.

Answer:

d) All of the above.

Explanation:

Explanation: Darwin’s theory of common descent is supported by various pieces of evidence including patterns in the fossil record, biogeographic distributions of species, and commonalities in embryological development across different species.

24. What is the relationship between the wing of a bird and the wing of a bat?

a) They are homologous because they represent modified forms of a trait present in a common ancestor (forelimbs).

b) They are analogous because while each carries out the same function (flight), this trait has arisen independently as a result of convergence (i.e. the common ancestor of both did not have a forelimb that allowed it to fly).

c) A and B.

d) They represent derived homologies.

Answer:

Explanation:

Explanation: While both bird and bat wings are used for flight, they are structurally different and evolved independently, hence they are analogous structures.

25. Which of the following is not an example of a macro evolutionary process?

a) One lion species splits to form two lion species over geological time.

b) The same trait evolves independently in two different taxa (e.g. wings in birds and in insects).

c) As a result of their activities, humans drive Dodos (a bird species) extinct.

d) Over a short period of time, the frequency of a single gene declines from 10 to 8%.

Answer:

d) Over a short period of time, the frequency of a single gene declines from 10 to 8%.

Explanation:

Explanation: Macroevolution involves large-scale evolutionary changes over long periods, whereas the decline in frequency of a single gene over a short period is a microevolutionary process.

26. The earliest organisms were ______

a) heterotrophic and anaerobic

b) autotrophic and anaerobic

c) heterotrophic and aerobic

d) autotrophic and aerobic

Answer:

a) heterotrophic and anaerobic

Explanation:

Explanation: The earliest organisms were likely heterotrophic and anaerobic as the primitive Earth’s atmosphere lacked oxygen.

27. Which one of the following is present today but was absent about 3.5 billion years ago ?

a) Oxygen

b) Nitrogen

c) Hydrogen

d) Methane

Answer:

a) Oxygen

Explanation:

Explanation: Oxygen began accumulating in the atmosphere after the evolution of photosynthesizing organisms, which occurred after the appearance of the earliest organisms.

28. Coacervates were experimentally produced by ______

a) Sydney Fox and Oparin

b) Fischer and Huxley

c) Jacob and Monod

d) Urey and Miller

Answer:

a) Sydney Fox and Oparin

Explanation:

Explanation: Coacervates, which are droplets that form spontaneously from the association of charged polymers, were experimentally produced by Oparin and were further studied by Sydney Fox.

29. Urey and Miller in their experiment used a mixture of gases corresponding to primitive earth. These were ______.

a) C3, NH3, H2, CO2

b) O2, NH3, CH4, H2

c) NH3, CH4, H2O, CO2

d) CH4, NH3, H2, H2O

Answer:

d) CH4, NH3, H2, H2O

Explanation:

Explanation: Urey and Miller used a mixture of gases — methane (CH4), ammonia (NH3), hydrogen (H2), and water vapor (H2O) — in their experiment to simulate the conditions of primitive Earth.

30. According to abiogenesis life originate from ______.

a) non-living matter

b) pre-exiting life

c) chemicals

d) extra-terrestrial matter

Answer:

a) non-living matter

Explanation:

Explanation: Abiogenesis is the theory that life originated from non-living matter through natural processes.

31. Mega – evolution is ______.

a) Changes in the gene pool

b) evolution due to mutations

c) origin of a new biological group

d) the evolution that takes centuries

Answer:

c) origin of a new biological group

Explanation:

Explanation: Mega-evolution refers to large-scale evolutionary changes that result in the origin of new biological groups over geological time frames.