Multiple Choice
Identify the letter of the choice that
best completes the statement or answers the question.
A
B
C
D
1.
The
rapid evolution of the surviving fragment of a population of chipmunks after a forest
fire
a.
must be caused by genetic
drift.
b.
cannot be caused
by genetic drift.
c.
might be caused by genetic
drift.
d.
none of the
above
A
B
C
D
2.
Which
factor most favors speciation?
a.
ecological competition
b.
geographic isolation
c.
gene pool stability
d.
a halt in evolution
A
B
C
D
3.
The
actual distribution of phenotypes for a typical polygenic trait
a.
is best expressed as a bar
graph.
b.
forms a
bell-shaped curve.
c.
exactly matches Mendelian
ratios.
d.
is similar to the
distribution of phenotypes of a single-gene trait.
A
B
C
D
4.
Mutations do NOT always affect
a.
genotype.
b.
phenotype.
c.
only single-gene traits.
d.
only polygenic traits.
A
B
C
D
5.
Sexual
reproduction
a.
affects
inheritable variation less than does mutation.
b.
produces many different
genotypes.
c.
does not affect
the number of phenotypes produced.
d.
alters the relative frequency of alleles in a
population.
A
B
C
D
6.
According to the Hardy-Weinberg principle, genetic equilibrium would be encouraged in
a population of deer mice, Peromyscus maniculatus , if
a.
the population size decreases.
b.
mutation rates within the population
rise.
c.
no natural
selection occurs.
d.
frequent movement both into and out of the population
occurs.
A
B
C
D
7.
An
example of a polygenic trait in humans is
a.
widow's peak.
b.
absence of widow's peak.
c.
height.
d.
ABO blood type.
A
B
C
D
8.
Most
inheritable differences are due to
a.
mutation.
b.
chemicals in the environment.
c.
gene shuffling.
d.
radiation.
A
B
C
D
9.
A
mutation that affects an organism's fitness must therefore affect the organism's
a.
genotype.
b.
phenotype.
c.
ability to reproduce.
d.
all of the above
A
B
C
D
10.
A new
species cannot form without
a.
different mating times.
b.
geographic barriers.
c.
different mating songs.
d.
reproductive isolation.
A
B
C
D
11.
A
change in a sequence of DNA is a
a.
recombination.
b.
polygenic trait.
c.
single-gene trait.
d.
mutation.
A
B
C
D
12.
In
genetic drift, allele frequencies change because of
a.
mutation.
b.
chance.
c.
natural selection.
d.
genetic equilibrium.
A
B
C
D
13.
Gene
shuffling includes the independent movement of chromosomes and
a.
the expression of polygenic
traits.
b.
the expression of
single-gene traits.
c.
crossing over.
d.
mutation.
A
B
C
D
14.
The
American toad breeds earlier in the spring than the Fowler's toad does. Therefore, they do not
interbreed, even though they often live in the same habitat. What can be inferred from this
information?
a.
The two species
do not interbreed because of geographic isolation.
b.
The two species do not interbreed because of temporal
isolation.
c.
The two species
undergo no ecological competition.
d.
Fowler's toad has a higher rate of survival than the
American toad does.
A
B
C
D
15.
The
Galápagos finches are an excellent example of
a.
speciation.
b.
genetic equilibrium.
c.
stabilizing selection.
d.
selection on single-gene traits.
A
B
C
D
16.
The
combined genetic information of all members of a population is the population's
a.
relative frequency.
b.
phenotype.
c.
genotype.
d.
gene pool.
A
B
C
D
17.
Interbreeding among members of a population
a.
alters the relative frequencies of alleles in the gene
pool.
b.
alters the
different types of alleles in the gene pool.
c.
does not alter the different types of alleles in the gene
pool.
d.
does not alter
genetic variation in the population.
A
B
C
D
18.
All
members of a population
a.
are temporally isolated.
b.
are geographically isolated.
c.
are able to interbreed.
d.
have identical genes.
A
B
C
D
19.
Genetic drift tends to occur
a.
in very large populations.
b.
in small populations.
c.
only in new species.
d.
following stabilizing selection.
A
B
C
D
20.
Populations are separated by barriers such as rivers, mountains, or bodies of water
in
a.
temporal isolation.
b.
geographic isolation.
c.
behavioral isolation.
d.
natural selection.
A
B
C
D
21.
Natural selection acts directly on
a.
alleles.
b.
genes.
c.
phenotypes.
d.
mutations.
A
B
C
D
22.
The
genetic equilibrium of a population can be disturbed by each of the following EXCEPT
a.
nonrandom mating.
b.
movement into and out of the
population.
c.
a large
population size.
d.
mutations.
A
B
C
D
23.
One of
the conditions required to maintain genetic equilibrium is
a.
natural selection.
b.
mutations.
c.
nonrandom mating.
d.
no movement into or out of the
population.
A
B
C
D
24.
The
situation in which allele frequencies remain constant is called
a.
evolution.
b.
genetic drift.
c.
genetic equilibrium.
d.
natural selection.
A
B
C
D
25.
Which
factor would most likely cause evolution in a large population?
a.
the production of large numbers of offspring within the
population
b.
the occurrence of
nonrandom mating within the population
c.
the absence of movement into and out of the
population
d.
the absence of
mutations within the population
