Biology 191 Final Exam Review questions
with correct answers
During a study session about evolution, one of your fellow students remarks, "The giraffe
stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a
result." Which statement is most likely to be helpful in correcting this student's
misconception? - verified answers; Characteristics acquired during an organism's life are
generally not passed on through genes.
Charles Darwin was the first person to propose - verified answers; a mechanism for evolution
that was supported by evidence
Which of these conditions should completely prevent the occurrence of a natural selection in
a population over time? - verified answers; All variation between individuals is due only to
environmental factors
Natural selection is based on all the following except - verified answers; individuals adapt to
their environments and thereby, evolove.
Given a population that contains genetic variation, what is the correct sequence of the
following events, under the influence of the natural selection?
1. well-adapted individuals leave more offspring than do poorly adapted individuals.
2. A change occurs in the environment
3. Genetic frequencies within the population change.
4. Poorly adapted individuals have decreased survivorship. - verified answers; 2-4-1-3
The roles that humans play in artificial selection is to - verified answers; choose which
organisms breed and which do not
,DDT was once considered a ʺsilver bulletʺ that would permanently eradicate insect pests.
Today, instead, DDT
is largely useless against many insects. Which of these would have been required for this pest
eradication effort
to be successful in the long run? - verified answers; None of the individual insects should have
processed genomes that made them resistant to DDT.
Which of the following pairs are the best examples of homologous structures? - verified
answers; bones in the bat wing and bones in the human forelimb
If two modern organisms are distantly related in an evolutionary sense, then one should
expect that - verified answers; they should share fewer homologous structures than two more
closely related organisms.
Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have
lost their digestive systems. Whales have lost their hind limbs. How can natural selection
account for these losses? - verified answers; Under particular circumstances that persisted for
long periods, each of these structures presented greater costs than benefits.
Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser
panda in the raccoon family (Procyonidae). Consequently, the morphological similarities of
these two species are probably due to - verified answers; possession of analogous structures
If organisms A, B, and C belong to the same class but to different orders and if organisms D, E,
and F belong to the same order but to different families, which of the following pairs of
organisms would be expected to show the greatest degree of structural homology? - verified
answers; D and F
, Which statement represents the best explanation for the observation that the nuclear DNA of
wolves and domestic dogs has a very high degree of sequence homology - verified answers;
Dogs and wolves belong to the same order
The common ancestors of birds and mammals were very early (stem) reptiles, which almost
certainty possessed three- chambered hearts (two atria, one ventricle). Birds and mammals,
however, are alike in having four-chambered hearts (two atria, two ventricles). The four-
chambered hearts of bird and mammals are described as - verified answers; homoplasies
The various taxonomic levels of the hierarchical classification system differ from each other
on the basis - verified answers; their inclusiveness
The most important feature that permits a gene to act as a molecular clock is - verified
answers; having a reliable average rate of mutation.
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the
frequency of the allele a is 0.3. What is the percentage of the population that is homozygous
for this allele? - verified answers; 49.0
In the formula for determining a population's genotype frequencies, the 2 in the term 2pq is
necessary because - verified answers; heterozygotes can come about in two ways
If, on average, 46% of the loci in a species' gene pool are heterozygous, then the average
homozygosity of the species should be - verified answers; 54%
Although each of the following has a better chance of influencing gene frequencies in small
populations than in large populations, which one most consistently requires a small
population as a precondition for its occurrence? - verified answers; genetic drift
Over time, the movement of people on Earth has steadily increased. This has altered the
course of human evolution by increasing - verified answers; gene flow
with correct answers
During a study session about evolution, one of your fellow students remarks, "The giraffe
stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a
result." Which statement is most likely to be helpful in correcting this student's
misconception? - verified answers; Characteristics acquired during an organism's life are
generally not passed on through genes.
Charles Darwin was the first person to propose - verified answers; a mechanism for evolution
that was supported by evidence
Which of these conditions should completely prevent the occurrence of a natural selection in
a population over time? - verified answers; All variation between individuals is due only to
environmental factors
Natural selection is based on all the following except - verified answers; individuals adapt to
their environments and thereby, evolove.
Given a population that contains genetic variation, what is the correct sequence of the
following events, under the influence of the natural selection?
1. well-adapted individuals leave more offspring than do poorly adapted individuals.
2. A change occurs in the environment
3. Genetic frequencies within the population change.
4. Poorly adapted individuals have decreased survivorship. - verified answers; 2-4-1-3
The roles that humans play in artificial selection is to - verified answers; choose which
organisms breed and which do not
,DDT was once considered a ʺsilver bulletʺ that would permanently eradicate insect pests.
Today, instead, DDT
is largely useless against many insects. Which of these would have been required for this pest
eradication effort
to be successful in the long run? - verified answers; None of the individual insects should have
processed genomes that made them resistant to DDT.
Which of the following pairs are the best examples of homologous structures? - verified
answers; bones in the bat wing and bones in the human forelimb
If two modern organisms are distantly related in an evolutionary sense, then one should
expect that - verified answers; they should share fewer homologous structures than two more
closely related organisms.
Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have
lost their digestive systems. Whales have lost their hind limbs. How can natural selection
account for these losses? - verified answers; Under particular circumstances that persisted for
long periods, each of these structures presented greater costs than benefits.
Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser
panda in the raccoon family (Procyonidae). Consequently, the morphological similarities of
these two species are probably due to - verified answers; possession of analogous structures
If organisms A, B, and C belong to the same class but to different orders and if organisms D, E,
and F belong to the same order but to different families, which of the following pairs of
organisms would be expected to show the greatest degree of structural homology? - verified
answers; D and F
, Which statement represents the best explanation for the observation that the nuclear DNA of
wolves and domestic dogs has a very high degree of sequence homology - verified answers;
Dogs and wolves belong to the same order
The common ancestors of birds and mammals were very early (stem) reptiles, which almost
certainty possessed three- chambered hearts (two atria, one ventricle). Birds and mammals,
however, are alike in having four-chambered hearts (two atria, two ventricles). The four-
chambered hearts of bird and mammals are described as - verified answers; homoplasies
The various taxonomic levels of the hierarchical classification system differ from each other
on the basis - verified answers; their inclusiveness
The most important feature that permits a gene to act as a molecular clock is - verified
answers; having a reliable average rate of mutation.
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the
frequency of the allele a is 0.3. What is the percentage of the population that is homozygous
for this allele? - verified answers; 49.0
In the formula for determining a population's genotype frequencies, the 2 in the term 2pq is
necessary because - verified answers; heterozygotes can come about in two ways
If, on average, 46% of the loci in a species' gene pool are heterozygous, then the average
homozygosity of the species should be - verified answers; 54%
Although each of the following has a better chance of influencing gene frequencies in small
populations than in large populations, which one most consistently requires a small
population as a precondition for its occurrence? - verified answers; genetic drift
Over time, the movement of people on Earth has steadily increased. This has altered the
course of human evolution by increasing - verified answers; gene flow
