BSC 108 Final Exam CH 13-20 Study
Area Questions All Solved 2026-2027
Updated.
The processes of __________ and __________ generate variation, and _________ produces
adaptation to the environment. - Answer mutation; sexual reproduction; natural selection
As a mechanism of evolution, natural selection can be most closely equated with __________. -
Answer unequal reproductive success.
If an insecticide killed all of the insect pests in a particular population, could insecticide
resistance evolve in this insect population? - Answer No, because there are no remaining
insects in this population to pass on beneficial alleles to the next generation
Why is it that isolated islands, such as the Hawaiian islands, often have many endemic
organisms (found nowhere else)? - Answer Organisms evolve in isolation because of the
difficulty of genetic exchange with other populations in distant locations.
An important challenge to traditional (pre-1860) ideas about species was the observation that
seemingly dissimilar organisms, such as hummingbirds, humans, and whales, have similar
skeletal structures. This most directly suggested to biologists that __________. - Answer
dissimilar organisms might have evolved from a distant, common ancestor
All known organisms translate genetic information to protein molecules via the same genetic
code. This finding strongly supports the hypothesis that __________. - Answer all organisms
are descended from a single common ancestor
"Differential success in reproduction associated with different inherited traits" is just another
way of saying __________. - Answer natural selection
"Natural selection" and "evolution" are two terms that are sometimes confused, even by
freshman biology students. What is the relation between natural selection and evolution? -
Answer Natural selection is one of several mechanisms of evolution.
If members of a population have traits that are both heritable and variable among individuals,
then __________. - Answer advantageous traits may become more widespread in subsequent
generations
When they were first sold, aerosol insecticides were highly effective in killing flies and
mosquitoes. Today, some 30 years later, a much smaller proportion of these insects die when
, sprayed. The reason fewer insects are being killed is that __________. - Answer many
mosquitoes today are descendants of mosquitoes with insecticide-resistant characteristics
Each of us is part of the ongoing evolution of the human species. Which of the following
occurrences would have the greatest impact on the future biological evolution of the human
population? - Answer A mutation occurs in one of your sperm or egg cells.
Suppose that, with regard to a particular genetic locus for which there are only two alleles, A
and a in a large population, we know that 60% of the alleles in the gene pool are A. Suppose
further that we observe this population for five generations, during which we know that no
mutation, selection, or migration has occurred. After this period, the frequency of the a allele is
expected to be __________. - Answer 0.4
Approximately 1 out of every 2,500 Caucasians in the United States is born with the recessive
disease cystic fibrosis. According to the Hardy-Weinberg equilibrium equation, approximately
how many people are carriers? - Answer 1 in 25
If a population is in Hardy-Weinberg equilibrium and remains in equilibrium, which of the
following will be true? - Answer There will be no mutations.
The evolutionary effects of genetic drift are greatest when __________. - Answer the
population size is small
The severe reduction in genetic variability seen in the endangered cheetah is probably
attributable to __________. - Answer having gone through at least one bottleneck
Birds with average-sized wings survived a severe storm more successfully than other birds in the
same population with longer or shorter wings. This illustrates __________. - Answer stabilizing
selection
A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into
burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in
the area tend to be very small or very large. What process is responsible for this outcome? -
Answer disruptive selection
Evolution of antibiotic resistance in bacteria is an example of which of the following? - Answer
directional selection
Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species that lived
side by side in parts of their ranges. However, recent books show them as eastern and western
forms of a single species, the yellow-rumped warbler. Apparently, the myrtle warbler and
Audubon's warbler __________. - Answer successfully interbreed and produce fertile offspring
Area Questions All Solved 2026-2027
Updated.
The processes of __________ and __________ generate variation, and _________ produces
adaptation to the environment. - Answer mutation; sexual reproduction; natural selection
As a mechanism of evolution, natural selection can be most closely equated with __________. -
Answer unequal reproductive success.
If an insecticide killed all of the insect pests in a particular population, could insecticide
resistance evolve in this insect population? - Answer No, because there are no remaining
insects in this population to pass on beneficial alleles to the next generation
Why is it that isolated islands, such as the Hawaiian islands, often have many endemic
organisms (found nowhere else)? - Answer Organisms evolve in isolation because of the
difficulty of genetic exchange with other populations in distant locations.
An important challenge to traditional (pre-1860) ideas about species was the observation that
seemingly dissimilar organisms, such as hummingbirds, humans, and whales, have similar
skeletal structures. This most directly suggested to biologists that __________. - Answer
dissimilar organisms might have evolved from a distant, common ancestor
All known organisms translate genetic information to protein molecules via the same genetic
code. This finding strongly supports the hypothesis that __________. - Answer all organisms
are descended from a single common ancestor
"Differential success in reproduction associated with different inherited traits" is just another
way of saying __________. - Answer natural selection
"Natural selection" and "evolution" are two terms that are sometimes confused, even by
freshman biology students. What is the relation between natural selection and evolution? -
Answer Natural selection is one of several mechanisms of evolution.
If members of a population have traits that are both heritable and variable among individuals,
then __________. - Answer advantageous traits may become more widespread in subsequent
generations
When they were first sold, aerosol insecticides were highly effective in killing flies and
mosquitoes. Today, some 30 years later, a much smaller proportion of these insects die when
, sprayed. The reason fewer insects are being killed is that __________. - Answer many
mosquitoes today are descendants of mosquitoes with insecticide-resistant characteristics
Each of us is part of the ongoing evolution of the human species. Which of the following
occurrences would have the greatest impact on the future biological evolution of the human
population? - Answer A mutation occurs in one of your sperm or egg cells.
Suppose that, with regard to a particular genetic locus for which there are only two alleles, A
and a in a large population, we know that 60% of the alleles in the gene pool are A. Suppose
further that we observe this population for five generations, during which we know that no
mutation, selection, or migration has occurred. After this period, the frequency of the a allele is
expected to be __________. - Answer 0.4
Approximately 1 out of every 2,500 Caucasians in the United States is born with the recessive
disease cystic fibrosis. According to the Hardy-Weinberg equilibrium equation, approximately
how many people are carriers? - Answer 1 in 25
If a population is in Hardy-Weinberg equilibrium and remains in equilibrium, which of the
following will be true? - Answer There will be no mutations.
The evolutionary effects of genetic drift are greatest when __________. - Answer the
population size is small
The severe reduction in genetic variability seen in the endangered cheetah is probably
attributable to __________. - Answer having gone through at least one bottleneck
Birds with average-sized wings survived a severe storm more successfully than other birds in the
same population with longer or shorter wings. This illustrates __________. - Answer stabilizing
selection
A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into
burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in
the area tend to be very small or very large. What process is responsible for this outcome? -
Answer disruptive selection
Evolution of antibiotic resistance in bacteria is an example of which of the following? - Answer
directional selection
Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species that lived
side by side in parts of their ranges. However, recent books show them as eastern and western
forms of a single species, the yellow-rumped warbler. Apparently, the myrtle warbler and
Audubon's warbler __________. - Answer successfully interbreed and produce fertile offspring
