exam 2: population genetics

Question 1

The null model for population genetics is

Answer 1

Hardy weinberg equilibrium

Question 2

Which of the following is an assumption of the Hardy–Weinberg model?

Answer 2

no mutation, random mating, no gene flow, infinite population size, and no selection

*Mating is random with respect to genotype.

Question 3

Consider a locus with only two alleles, A and a, in a population of diploid individuals. If
the frequencies of A and a in the population are p and q, respectively, then p + q =

Answer 3

1.0

Question 4

Consider a locus with two alleles, A and a. Under which of the following scenarios will
the frequency of the A allele increase?

Answer 4

The fitness of AA and Aa individuals are higher than the fitness of aa individuals.

Question 5

Which of the following would best help you predict the fate of an allele in a population

Answer 5

determine survival rates of individuals of each genotype

Question 6

Mathematical descriptions of evolutionary processes allow biologists to make ________
predictions about how genotype frequencies change over time

Answer 6

quantitative

Question 7

What kind of equilibrium does overdominance produce

Answer 7

stable

Question 8

Which of the following scenarios would make it hard for selection to eliminate the alleles
for undesirable traits

Answer 8

high gene flow between populations

Question 9

Natural selection can act on both ________, which is the probability of survival, and
________, which is the number of oƯspring produced.

Answer 9

viability ; fecundity

Question 10

Under ________, individuals tend to mate with others of the same genotype. Under
________, individuals tend to mate with others of diƯerent genotypes

Answer 10

assortative mating; disassortative mating

Question 11

Inbreeding increases the frequency of ________ in a population

Answer 11

homozygotes

Question 12

Which of the following processes will result in more heterozygotes than expected under
Hardy–Weinberg

Answer 12

disassortative mating

Question 13

Which of the following is a consequence of recessive deleterious alleles in a
population?

Answer 13

reduced fitness of the population when there is inbreeding

Question 14

. In the scenario depicted in the figure, what will happen to the allele frequencies on the
island? Assume there is no selection or mutation, mating is random, and the population sizes are
large

Answer 14

They will become more similar to those on the mainland.

Question 15

Which of the following processes can increase genetic variation in a population

Answer 15

mutation and migration

Question 16

In the early twentieth century, one of the criticisms of Mendel’s conclusions about
inheritance was that

Answer 16

the traits he studied showed discrete variation, while many traits in nature show continuous variation.

Question 17

Migration between two populations.

Answer 17

Migration, also called gene flow, occurs both with the advancing front of a population when it is colonizing new areas, and when genes of two or more populations mix through pollen and seed dispersa

Question 18

The figure shows the change in allele frequencies over many generations. What most
likely diƯers between the populations represented by the three lines

Answer 18

*Whether the allele is dominant or recesssive.
*the strength of selection