Q1. What is the process by which species of organisms arise and develop through the natural selection of small, inherited variations?
a) Adaptation
b) Evolution
c) Mutation
d) Hybridization
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Correct Answer: b) Evolution
Explanation: Evolution is the process of cumulative change in the heritable characteristics of a population. It occurs through the gradual accumulation of small genetic changes over many generations. Natural selection, genetic drift, and gene flow are some mechanisms driving evolution.
Q2. Which scientist is credited with proposing the theory of evolution by natural selection?
a) Isaac Newton
b) Charles Darwin
c) Albert Einstein
d) Gregor Mendel
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Correct Answer: b) Charles Darwin
Explanation: Charles Darwin, an English naturalist, proposed the theory of evolution by natural selection in his seminal work “On the Origin of Species,” published in 1859. His theory revolutionized the understanding of how species evolve over time.
Q3. Which of the following is not a mechanism of evolution?
a) Genetic drift
b) Lamarckism
c) Mutation
d) Gene flow
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Correct Answer: b) Lamarckism
Explanation: Lamarckism, proposed by Jean-Baptiste Lamarck, suggested that acquired traits can be passed on to offspring. However, this theory has been largely discredited in favor of Darwin’s theory of natural selection.
Q4. What term describes the process by which unrelated species evolve similar traits due to similar environmental pressures?
a) Convergent evolution
b) Divergent evolution
c) Adaptive radiation
d) Coevolution
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Correct Answer: a) Convergent evolution
Explanation: Convergent evolution occurs when unrelated species independently evolve similar traits due to similar environmental pressures. This results in analogous structures that serve similar functions but have different evolutionary origins.
Q5. Which type of selection favors extreme phenotypes over the average phenotype in a population?
a) Stabilizing selection
b) Disruptive selection
c) Directional selection
d) Balancing selection
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Correct Answer: c) Directional selection
Explanation: Directional selection occurs when environmental conditions favor individuals with phenotypes that are at one extreme of the population distribution. Over time, this shifts the average phenotype towards that extreme, leading to evolutionary change.
Q6. What is the primary source of genetic variation upon which natural selection acts?
a) Mutation
b) Genetic drift
c) Gene flow
d) Genetic recombination
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Correct Answer: a) Mutation
Explanation: Mutations are random changes in the DNA sequence that can lead to new genetic variations. These variations provide the raw material upon which natural selection acts, allowing individuals with advantageous mutations to survive and reproduce.
Q7. Which of the following is an example of anatomical evidence for evolution?
a) Homologous structures
b) Analogous structures
c) Vestigial organs
d) All of the above
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Correct Answer: d) All of the above
Explanation: Homologous structures are similar in structure but have different functions, suggesting a common ancestor. Analogous structures perform similar functions but have different evolutionary origins. Vestigial organs are remnants of structures that were functional in ancestral organisms but are reduced or non-functional in descendants, providing evidence of evolution.
Q8. Which scientist proposed the theory of punctuated equilibrium as an alternative to gradualism in evolution?
a) Charles Darwin
b) Alfred Russel Wallace
c) Stephen Jay Gould
d) Richard Dawkins
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Correct Answer: c) Stephen Jay Gould
Explanation: Stephen Jay Gould, along with Niles Eldredge, proposed the theory of punctuated equilibrium in 1972. This theory suggests that evolution is characterized by long periods of stasis punctuated by rapid bursts of change, contrasting with the gradualism proposed by Darwin.
Q9. Which term describes the evolutionary process by which two or more species reciprocally affect each other’s evolution?
a) Convergent evolution
b) Divergent evolution
c) Coevolution
d) Adaptive radiation
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Correct Answer: c) Coevolution
Explanation: Coevolution occurs when two or more species influence each other’s evolution through reciprocal interactions, such as predation, competition, or mutualism. This leads to a continuous evolutionary arms race between interacting species.
Q10. Which type of selection favors the average phenotype in a population, reducing genetic variation?
a) Stabilizing selection
b) Disruptive selection
c) Directional selection
d) Balancing selection
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Correct Answer: a) Stabilizing selection
Explanation: Stabilizing selection occurs when intermediate phenotypes are favored over extreme phenotypes, reducing genetic variation in the population. This type of selection tends to maintain the status quo of a population’s characteristics over time.