Questions on Forces of Evolution
Multiple-Choice Questions: Forces of Evolution
1. Which of the following is NOT considered a force of evolution?
A) Mutation
B) Genetic drift
C) Natural selection
D) Gene flow
E) Photosynthesis
2. What is the role of mutation in evolution?
A) To remove harmful alleles
B) To create new genetic variation
C) To maintain allele frequencies constant
D) To increase population size
E) To cause extinction
3. How does natural selection influence evolution?
A) By randomly changing allele frequencies
B) By favoring individuals with advantageous traits
C) By moving alleles between populations
D) By causing mutations
E) By stabilizing population size
4. What does genetic drift refer to?
A) Non-random mating
B) Random changes in allele frequencies due to chance
C) Selection of beneficial mutations
D) Gene exchange between populations
E) Mutation accumulation
5. Which population is most affected by genetic drift?
A) Large populations
B) Small populations
C) Populations with high mutation rates
D) Populations with no migration
E) Populations with random mating
6. What is gene flow?
A) Movement of alleles between populations due to migration
B) Random mutation
C) Selection of advantageous alleles
D) Genetic drift in isolated populations
E) Reproduction rate increase
7. What effect does gene flow have on populations?
A) Increases genetic differences between populations
B) Decreases genetic differences between populations
C) Causes extinction
D) Eliminates mutation
E) Stops natural selection
8. What is an example of directional selection?
A) Both extremes of a trait are favored
B) Intermediate trait is favored
C) One extreme trait is favored
D) No change in trait distribution
E) Random change in trait distribution
9. What type of selection favors the average phenotype?
A) Directional selection
B) Stabilizing selection
C) Disruptive selection
D) Sexual selection
E) Artificial selection
10. What type of selection favors both extremes of a trait but selects against the average?
A) Directional selection
B) Stabilizing selection
C) Disruptive selection
D) Sexual selection
E) Genetic drift
11. How does sexual selection differ from natural selection?
A) It acts only on mutation rates
B) It selects traits related to mate attraction and reproduction
C) It causes gene flow
D) It only affects small populations
E) It is random
12. What is the bottleneck effect?
A) When a few individuals start a new population
B) A sudden reduction in population size causing loss of genetic variation
C) Gene flow between populations
D) Mutation spreading rapidly
E) Selection of beneficial alleles
13. What is the founder effect?
A) Gene flow caused by migration
B) When a small group starts a new population with limited genetic variation
C) Sudden population increase
D) Stabilizing selection
E) Mutation accumulation
14. Which force of evolution introduces new alleles into a population?
A) Genetic drift
B) Mutation
C) Gene flow
D) Natural selection
E) Bottleneck effect
15. How can genetic drift lead to loss of genetic diversity?
A) By increasing mutation rate
B) By random loss of alleles especially in small populations
C) By increasing gene flow
D) By natural selection
E) By stabilizing allele frequencies
16. Which force of evolution tends to make populations more genetically similar?
A) Mutation
B) Genetic drift
C) Gene flow
D) Natural selection
E) Bottleneck effect
17. What is the main consequence of stabilizing selection on genetic variation?
A) Increases variation
B) Decreases variation by favoring intermediate traits
C) No change in variation
D) Increases mutation rate
E) Causes speciation
18. How can natural selection lead to adaptation?
A) By random chance
B) By favoring traits that increase survival and reproduction
C) By increasing mutation rate
D) By migration
E) By genetic drift
19. Which force of evolution is mostly responsible for rapid changes in allele frequencies in small populations?
A) Mutation
B) Natural selection
C) Genetic drift
D) Gene flow
E) Sexual selection
20. What happens to allele frequencies in a population with no evolutionary forces acting?
A) They change rapidly
B) They remain constant
C) They increase mutation rate
D) They increase genetic drift
E) They fluctuate randomly
Questions on Hardy-Weinberg Principle
Questions on Population Genetics
Answer Key with Explanations
1. E – Photosynthesis is a biological process, not a force of evolution.
2. B – Mutation creates new genetic variation, the raw material for evolution.
3. B – Natural selection favors individuals with traits that increase fitness.
4. B – Genetic drift is a random change in allele frequencies by chance.
5. B – Small populations are more affected by genetic drift.
6. A – Gene flow is allele movement due to migration between populations.
7. B – Gene flow decreases genetic differences by mixing alleles.
8. C – Directional selection favors one extreme phenotype.
9. B – Stabilizing selection favors the average phenotype.
10. C – Disruptive selection favors both extremes, against the average.
11. B – Sexual selection acts on traits important for attracting mates.
12. B – Bottleneck effect is a sudden population reduction causing loss of diversity.
13. B – Founder effect occurs when a small group starts a new population with limited variation.
14. B – Mutation introduces new alleles into the gene pool.
15. B – Genetic drift randomly removes alleles, reducing diversity especially in small populations.
16. C – Gene flow homogenizes populations, making them genetically more similar.
17. B – Stabilizing selection reduces variation by favoring intermediate traits.
18. B – Adaptation results from natural selection favoring beneficial traits.
19. C – Genetic drift causes rapid allele frequency changes in small populations.
20. B – Without evolutionary forces, allele frequencies remain constant (Hardy-Weinberg equilibrium).
Dive into the groundbreaking science of neurotransmitters—your brain’s invisible architects—in Chemical Harmony: How Neurotransmitters Shape Our Lives (2025). This meticulously researched book reveals how serotonin, dopamine, GABA, and other brain chemicals silently orchestrate every aspect of your existence, from decision-making and relationships to mental health and emotional resilience.Click here to buy
👉 +3000 Biology Questions with Answers Key.
Share Online!
