Q: A population of 1000 birds has two alleles for feather color: $$B$$ and $$b. If$$ $$B is $$dominant and the frequency of $$B is$$ $$p = 0.6$$, what is the expected frequency of heterozygotes under Hardy-Weinberg equilibrium?

$$2pq = 2 \times 0.6 \times 0.4 = 0.48$$

Question 1

Which of the following best describes the effect of genetic drift on small populations?

Accepted Answer

Genetic drift can lead to a loss of genetic variation and fixation of alleles.

Question 2

In the context of the bottleneck effect, what is the most likely outcome for a population that has passed through a drastic reduction in size?

Accepted Answer

The population will have reduced genetic variation and may overrepresent certain alleles.

Question 3

Which equation represents the Hardy-Weinberg equilibrium for allele frequencies in a population?

Accepted Answer

$$p^2 + 2pq$$ + $$q^2 = 1$

Question 4

A population of wildflowers has the following allele frequencies: $$p = 0.7$$ and $$q = 0.3. If $$only 5 out of 10 plants leave offspring, and by chance only two plants in the next generation are fertile, what is the most likely effect on allele frequencies?

Accepted Answer

Allele frequencies will fluctuate randomly, potentially leading to fixation or loss of alleles.

Question 5

Which of the following is NOT a condition required for Hardy-Weinberg equilibrium?

Accepted Answer

Natural selection

Question 6

The founder effect occurs when:

Accepted Answer

A few individuals colonize a new habitat, leading to altered allele frequencies.

Question 7

In the case of the Illinois greater prairie chicken, what was the primary consequence of genetic drift after the population bottleneck?

Accepted Answer

Decrease in hatching rates due to loss of genetic variation

Question 8

Which real-world example illustrates the bottleneck effect and its impact on genetic variation?

Accepted Answer

The Florida panther population

Question 9

Gene flow is best described as:

Accepted Answer

The transfer of alleles between populations, reducing genetic differences

Question 10

Which scenario would most likely lead to adaptive evolution?

Accepted Answer

Natural selection consistently favors traits that enhance survival and reproduction

Question 11

In the Lake Erie water snake example, what prevents the complete loss of banding in island populations?

Accepted Answer

Gene flow from mainland populations introduces banding alleles

Question 12

Which of the following statements about genetic drift is TRUE?

Accepted Answer

Genetic drift can lead to the fixation or loss of alleles at random.

Question 13

If a population is not in Hardy-Weinberg equilibrium, which of the following could be a possible cause?

Accepted Answer

Gene flow between populations

Question 14

Which process is most likely to reduce genetic differences between two populations?

Accepted Answer

Gene flow

Question 15

A population of 1000 birds has two alleles for feather color: $$B$$ and $$b. If$$ $$B is $$dominant and the frequency of $$B is$$ $$p = 0.6$$, what is the expected frequency of heterozygotes under Hardy-Weinberg equilibrium?

Accepted Answer

$$2pq = 2 	imes 0.6 	imes 0.4 = 0.48$$

Question 16

Which of the following best explains why genetic drift can have a greater impact on small populations than on large populations?

Accepted Answer

Random events can cause large changes in allele frequencies in small populations.

Question 17

What is the primary consequence of the bottleneck effect for endangered species?

Accepted Answer

Loss of genetic variation, making the population more vulnerable to environmental changes

Question 18

Which of the following is an example of gene flow affecting local adaptation?

Accepted Answer

Banded snakes on the mainland and unbanded snakes on islands, with gene flow maintaining banding alleles on islands

Question 19

If a storm blows a few individuals from a mainland population to a new island, what evolutionary process is most likely to occur?

Accepted Answer

Founder effect

Question 20

Which statement best summarizes the relationship between genetic drift and population size?

Accepted Answer

Genetic drift is more significant in small populations, leading to random changes in allele frequencies.

Mechanisms of Evolution: Genetic Drift, Bottlenecks, and Gene Flow

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