Biology

Sylvia S. Mader, Michael Windelspecht

Chapter 16

How Populations Evolve - all with Video Answers

Educators

JW

Chapter Questions

Problem 1

Assuming a Hardy-Weinberg equilibrium, 21% of a population
is homozygous dominant, 50% is heterozygous, and 29% is
homozygous recessive. What percentage of the next generation
is predicted to be homozygous recessive?
a. 21%
b. 50%
c. 29%
d. 42%
e. 58%

Justin Im

Justin Im

Numerade Educator

Problem 2

A human population has a higher than usual percentage of individuals with a genetic disorder. The most likely explanation is
a. mutations and gene flow.
b. mutations and natural selection.
c. nonrandom mating and founder effect.
d. nonrandom mating and gene flow.
e. All of these are correct

Justin Im

Numerade Educator

Problem 3

The offspring of better-adapted individuals are expected to make up a larger proportion of the next generation. The most likely explanation is
a. mutations and nonrandom mating.
b. gene flow and genetic drift.
c. mutations and natural selection.
d. mutations and genetic drift

Justin Im

Numerade Educator

Problem 4

When a population is small, there is a greater chance of
a. gene flow.
b. genetic drift.
c. natural selection.
d. mutations.
e. sexual selection

Justin Im

Numerade Educator

Problem 5

Which of the following cannot occur if a population is to maintain an equilibrium of allele frequencies?
a. People leave one country and relocate in another.
b. A disease wipes out the majority of a herd of deer.
c. Members of an Indian tribe allow only the two tallest people in the tribe to marry each spring.
d. Large black rats are the preferred males in a population of rats.
e. All of these are correct

Pete Motyka

Numerade Educator

Problem 6

Which of the following applies to the Hardy-Weinberg expression: $p^{2}+2 p q+q^{2} ?$
a. Knowing either $p^{2}$ or $q^{2},$ you can calculate all the other frequencies.
b. It applies to Mendelian traits that are controlled by one pail of alleles.
c. $2 p q=$ heterozygous individuals
d. It can be used to determine the genotype and allele frequencies of the previous and the next generations.
e. All of these are correct.

Justin Im

Numerade Educator

Problem 7

Following genetic drift,
a. genotype and allele frequencies would not change.
b. genotype and allele frequencies would change.
c. adaptation would occur.
d. the population would have more phenotypic variation but less genotypic variation.

Justin Im

Numerade Educator

Problem 8

Which of the following is an example of stabilizing selection?
a. Over time, Equus developed strength, intelligence, speed, and durable grinding teeth.
b. British land snails mainly have two different phenotypes.
c. Swiss starlings usually lay four or five eggs, thereby increasing their chances of more offspring.
d. Drug resistance increases with each generation; the resistant bacteria survive, and the nonresistant bacteria get killed off.
e. All of these are correct

Justin Im

Numerade Educator

Problem 9

One way for disruptive selection to occur is if
a. the population contains diversity.
b. the environment contains diversity.
c. pollution is present.
d. natural selection occurs.
e. All of these are correct.

Justin Im

Numerade Educator

Problem 10

In some bird species, the female chooses a mate that is most similar to her in size. This supports
a. the good genes hypothesis.
b. the runaway hypothesis.
c. the sexual dimorphism hypothesis.
d. All of these hypotheses could be true.
e. None of these hypotheses are true

JW

Jardon Weems

Numerade Educator

Problem 11

A red deer harem master typically dies earlier than other males because
a. he will likely be expelled from the herd and cannot survive alone.
b. he will be more prone to disease because he interacts with so many animals.
c. he needs more food than other males.
d. he is apt to place himself between a predator and the herd to protect the herd.
e. he inherited the genetics for a shorter lifespan.

Justin Im

Numerade Educator

Problem 12

The continued occurrence of sickle-cell disease with malaria in
parts of Africa is due to
a. continual mutation.
b. gene flow between populations.
c. relative fitness of the heterozygote
d. disruptive selection.
e. protozoan resistance to DDT.

Justin Im

Numerade Educator

Problem 13

Which genotype is characteristic of the heterozygote advantage?
$$
\text { a. }H H \quad \text { b. } H h \quad \text { c. } h h \quad \text { d. } t a \quad \text { e. } H T
$$

Justin Im

Numerade Educator