1. What is gene flow?
A) Movement of individuals within a population
B) Movement of alleles between populations
C) Loss of genetic diversity due to small population size
D) Formation of new species
Answer: B) Movement of alleles between populations
2. Which of the following is an example of genetic drift?
A) Mutation introducing a new trait in a population
B) Founder effect leading to reduced genetic variation
C) Migration introducing new alleles into a population
D) Selection of advantageous traits by the environment
Answer: B) Founder effect leading to reduced genetic variation
3. The bottleneck effect occurs when:
A) A population undergoes a rapid increase in size
B) A large portion of the population is suddenly reduced
C) New mutations arise in a population
D) Individuals migrate to a new habitat
Answer: B) A large portion of the population is suddenly reduced
4. Genetic drift is most significant in:
A) Large populations
B) Small populations
C) Populations in Hardy-Weinberg equilibrium
D) Populations undergoing strong natural selection
Answer: B) Small populations
5. The introduction of genes from one population to another is termed:
A) Genetic drift
B) Gene flow
C) Mutation
D) Speciation
Answer: B) Gene flow
6. Which process decreases genetic variation within a population?
A) Gene flow
B) Natural selection
C) Genetic drift
D) Mutation
Answer: C) Genetic drift
7. What is the primary cause of the founder effect?
A) Migration of a small group to a new area
B) Sudden change in the environment
C) Reproductive isolation
D) High mutation rates
Answer: A) Migration of a small group to a new area
8. Gene flow tends to:
A) Increase genetic variation within populations
B) Decrease genetic variation within populations
C) Make populations genetically similar
D) Make populations genetically distinct
Answer: C) Make populations genetically similar
9. Which of the following contributes to genetic drift?
A) Large population size
B) Random sampling of alleles
C) High gene flow
D) Adaptive traits
Answer: B) Random sampling of alleles
10. Evolutionary changes due to genetic drift are:
A) Predictable and consistent
B) Non-directional and random
C) Based on natural selection
D) Due to high fitness alleles
Answer: B) Non-directional and random
11. A significant reduction in population size that affects allele frequencies is called:
A) Gene flow
B) Bottleneck effect
C) Founder effect
D) Mutation
Answer: B) Bottleneck effect
12. What happens to alleles in a small population during genetic drift?
A) Rare alleles always increase in frequency
B) Allele frequencies fluctuate randomly
C) All alleles are lost over time
D) Only beneficial alleles persist
Answer: B) Allele frequencies fluctuate randomly
13. Which process maintains genetic diversity in a population?
A) Inbreeding
B) Gene flow
C) Bottleneck effect
D) Founder effect
Answer: B) Gene flow
14. Genetic drift often leads to:
A) Increased genetic variation
B) Adaptation to the environment
C) Loss of genetic variation
D) Increased gene flow
Answer: C) Loss of genetic variation
15. Gene flow can counteract the effects of:
A) Natural selection
B) Genetic drift
C) Mutation
D) Speciation
Answer: B) Genetic drift
16. Speciation occurs when:
A) Populations remain connected by gene flow
B) Genetic drift and natural selection result in reproductive isolation
C) Mutation rates are low
D) Environmental factors stabilize allele frequencies
Answer: B) Genetic drift and natural selection result in reproductive isolation
17. Which of the following is not an example of evolutionary change?
A) Change in allele frequency over time
B) Genetic drift in small populations
C) Gene flow between isolated populations
D) Random mating without selection
Answer: D) Random mating without selection
18. Genetic drift affects:
A) Large populations more than small populations
B) Both large and small populations equally
C) Small populations more than large populations
D) Populations with high gene flow
Answer: C) Small populations more than large populations
19. The Hardy-Weinberg principle assumes:
A) High levels of genetic drift
B) No gene flow
C) Rapid mutation rates
D) Unequal reproductive success
Answer: B) No gene flow
20. Adaptive evolution is primarily driven by:
A) Genetic drift
B) Gene flow
C) Mutation
D) Natural selection
Answer: D) Natural selection
21. Which factor does not affect allele frequency in a population?
A) Mutation
B) Gene flow
C) Neutral traits
D) Genetic drift
Answer: C) Neutral traits
22. When individuals with similar genotypes preferentially mate with one another, it is called:
A) Genetic drift
B) Inbreeding
C) Gene flow
D) Natural selection
Answer: B) Inbreeding
23. Genetic drift can lead to:
A) Fixation of alleles
B) Increased mutation rates
C) High genetic variation
D) Speciation without isolation
Answer: A) Fixation of alleles
24. Evolution is defined as:
A) Changes in phenotype frequency
B) Changes in allele frequency over generations
C) Increase in population size over time
D) Development of new traits
Answer: B) Changes in allele frequency over generations
25. Natural selection acts on:
A) Genotypes directly
B) Phenotypes expressed in organisms
C) Mutations in DNA sequences
D) Random changes in population size
Answer: B) Phenotypes expressed in organisms
26. Gene flow can increase genetic variation by:
A) Introducing new alleles into a population
B) Removing harmful mutations
C) Fixing advantageous traits
D) Preventing natural selection
Answer: A) Introducing new alleles into a population
27. Which is an example of genetic drift in action?
A) A forest fire reducing population size
B) A new predator introducing natural selection
C) A mutation creating a new trait
D) Migration of individuals between populations
Answer: A) A forest fire reducing population size
28. Natural selection is different from genetic drift because it:
A) Is random in nature
B) Acts on population size
C) Promotes adaptation to the environment
D) Affects only small populations
Answer: C) Promotes adaptation to the environment
29. Loss of genetic variation due to random events is called:
A) Mutation
B) Gene flow
C) Genetic drift
D) Natural selection
Answer: C) Genetic drift
30. The concept that evolution occurs due to cumulative small changes is called:
A) Gradualism
B) Genetic drift
C) Punctuated equilibrium
D) Gene flow
Answer: A) Gradualism
