CLEP Biology Mechanisms of Natural Selection 2

Question 1

Which condition is NOT required for Hardy-Weinberg equilibrium to apply to a population?

Accepted Answer

Small population size

Answer

Random mating

Answer

No natural selection

Answer

No gene flow

Question 2

A cheetah population that went through a severe bottleneck event would most likely show:

Accepted Answer

Reduced genetic variation

Answer

High genetic diversity

Answer

Increased mutation rate

Answer

Greater phenotypic variation

Question 3

Disruptive selection in a population tends to:

Accepted Answer

Favor both extreme phenotypes

Answer

Favor intermediate phenotypes

Answer

Reduce phenotypic variation

Answer

Favor only the largest individuals

Question 4

Industrial melanism in peppered moths is a classic example of which evolutionary mechanism?

Accepted Answer

Directional selection

Answer

Genetic drift

Answer

Founder effect

Answer

Balancing selection

Question 5

Which statement best describes stabilizing selection?

Accepted Answer

It reduces variation by favoring intermediate phenotypes

Answer

It increases variation in a population over time

Answer

It favors extreme phenotypes at both ends

Answer

It only operates in sexually reproducing species

Question 6

Gene flow between two previously isolated populations would most likely:

Accepted Answer

Decrease genetic differences between them

Answer

Increase genetic differences between them

Answer

Cause speciation

Answer

Have no effect on allele frequencies

Question 7

Which best explains why recessive deleterious alleles persist in a population rather than being eliminated?

Accepted Answer

Natural selection cannot act on hidden recessive alleles in heterozygotes

Answer

They are beneficial in heterozygous form

Answer

Mutations continuously recreate them at high rates

Answer

They are always co-dominant with the dominant allele