Name_______________________
Ch 13 & 14 homework
Ch 13
1. What are homologous structures? Give an example of a pair of homologous structures
2. A population is
a. a group of individuals of the same species living in the same place at the same
time.
b. all individuals of a species, regardless of location or time period in which they
live.
c. a group of individuals of different species living in the same place at the same
time.
d. a group of individuals of a species plus all of the other species with which they
interact.
e. a group of species that share a common characteristic.
3. What were Darwin’s three key observations used to form his theory of evolution
4. Evolution acts on the ______________________ but affects the
____________________.
5. What 5 conditions must a population satisfy to remain in Hardy-Weinberg Equlibrium?
6. Genetic drift resulting from a disaster that drastically reduces population size is called (1
point)
A)
natural selection.
B)
gene flow.
C)
the bottleneck effect.
D)
nonrandom mating.
E)
the founder effect.
7. Frequency-dependent selection, as seen in the case of the scale-eating fish in Lake
Tanganyika, tends to
a.
eliminate rare alleles and favor whichever allele is initially most frequent.
b.
maintain two phenotypes in a dynamic equilibrium in a population.
c.
produce random changes in allele frequencies.
d.
lead to heterozygote advantage.
e.
stimulate new mutations.
8. What is neutral variation?
9. What are the three types of selection than can alter variation within a population? How
does each of them work? (2 points)
Ch 14
1) A biological species is defined as a group of organisms that
A) are physically similar.
B) are genetically similar.
C) share a recent common ancestor.
D) live together in a location and carry out identical ecological roles.
E) have the potential to interbreed in nature and produce fertile offspring.
2) Which provides the most general and correct description of the idea of a reproductive
barrier?
A) any feature (of geography, behavior, or morphology) that keeps one species from mating
with another
B) a biological difference between two species that prevents them from successfully
interbreeding
C) a geographic barrier that separates two species and prevents gene flow between them
D) a difference in reproductive biology between two species that makes hybrid individuals
less fertile
E) a difference in behavior that keeps two species from interbreeding
3) Which of the following types of reproductive barriers separates a pair of species that could
interbreed except that one mates at dusk and the other at dawn?
A) temporal isolation
B) habitat isolation
C) behavioral isolation
D) mechanical isolation
E) gametic isolation
4) Which of the following types of reproductive barriers separates two flowering plant species
that could interbreed except that one has a deep flower tube and is pollinated by bumblebees,
whereas the other has a short, narrow flower tube and is pollinated by honeybees?
A) temporal isolation
B) habitat isolation
C) behavioral isolation
D) mechanical isolation
E) gametic isolation
D) mechanical isolation
E) gametic isolation
5) A zebra and a donkey mate and have an zebroid offspring. The zebroid is vigorous but sterile.
This is an example of
A) mechanical isolation.
B) gametic isolation.
C) reduced hybrid fertility.
D) reduced hybrid viability.
E) hybrid breakdown.
6) Explain a prezygotic and postzygotic barrier.
7) What does the term punctuated equilibrium describe?
8) The Darwin’s finches on the Galapagos islands demonstrate adaptive radiation. Using them as
an example, explain how adaptive radiation leads to speciation.
9) Compare and contrast allopatric and sympatric speciation.