IB 150 Exam 3 Homework Questions With Complete
Solutions
_____________ is likely the most common mode of selection in
populations during long periods of stasis (lack of phenotypic
change).
Select one:
a. natural selection
b. sexual selection
c. directional selection
d. stabilizing selection
e. disruptive selection Correct Answers d. stabilizing selection
A particular recessive genetic disorder is fatal before birth, so
there are no homozygous recessive individuals. In a particular
population, one in 15 individuals is a carrier for this disorder.
What are the allele frequencies of the dominant (p) and recessive
(q) alleles in this population?
Select one:
a. p = 0.955, q = 0.045
b. p = 0.933, q = 0.067
c. p = 1.0, q = 0.0
d. p = 0.967, q = 0.033 Correct Answers d. p = 0.967, q = 0.033
Altruistic behavior (helping others without repayment) is a
human behavioral trait that is relatively uncommon in other
species, especially in cases like the adoption of an unrelated
orphaned child. Raising an unrelated child takes a large amount
of time and material resources that are hence not available to the
,raising of a biological offspring, so you might expect these
behaviors to be selected against if they had a heritable basis.
Evolutionary psychology nevertheless has tried to explain
altruistic behavior in humans as an adaptation, in other words as
a direct result of natural selection.
IF the hypothesis is correct that adoption of unrelated children
IS a human behavior that evolved as a result of natural selection,
which of the following scenarios would be consistent with this
explanation?
Select one:
a. Humans that lack the strong emotional feeling of empathy that
causes them to want to protect children (in Correct Answers b.
Humans that lack the strong emotional feeling of empathy that
causes them to want to protect children (including unrelated
ones) are more likely to lose biological offspring to accidents or
mishaps as well.
Claytonia virginica is a woodland spring herb with flowers that
vary from white to pale pink to bright pink. This plant is
primarily pollinated by a bee that prefers pink flowers to white
flowers. As a result, Claytonia with pink flowers have greater
relative fruit set than Claytonia with white flowers due to greater
pollination rates. Nevertheless, the percentage of different
flower colors remains stable in the study population from year to
year. Which of these statements might explain this observation?
Select one:
a. Reproductive success is not a good measure for fitness in this
species.
, b. Flower color is not heritable but is instead determined by the
pH of the soil.
c. Fitness is primarily determined by fruit set in this species.
d. The white flowers have evolved pollinator resistance. Correct
Answers b. Flower color is not heritable but is instead
determined by the pH of the soil.
Did the allele frequencies change from the original population in
Question 8 to your predicted offspring generation in Question 9?
Select one:
a. Yes
b. No Correct Answers b. No
IF your hypothesis in the previous question is correct, what else
can you predict as being likely true and might be able to explain
why the behavioral trait "strong empathy for an urge to protect
children" is so common in humans and not other species?
Select one:
a. Altruistic behavior cannot be a heritable trait in most other
species.
b. Most other species are not as smart as humans.
c. Altruistic behavior cannot be a heritable trait in humans.
d. Human babies are more vulnerable and in greater need of
parental care than in most other species.
e. Most other species are not capable of feeling empathy.
Correct Answers d. Human babies are more vulnerable and in
greater need of parental care than in most other species.
Solutions
_____________ is likely the most common mode of selection in
populations during long periods of stasis (lack of phenotypic
change).
Select one:
a. natural selection
b. sexual selection
c. directional selection
d. stabilizing selection
e. disruptive selection Correct Answers d. stabilizing selection
A particular recessive genetic disorder is fatal before birth, so
there are no homozygous recessive individuals. In a particular
population, one in 15 individuals is a carrier for this disorder.
What are the allele frequencies of the dominant (p) and recessive
(q) alleles in this population?
Select one:
a. p = 0.955, q = 0.045
b. p = 0.933, q = 0.067
c. p = 1.0, q = 0.0
d. p = 0.967, q = 0.033 Correct Answers d. p = 0.967, q = 0.033
Altruistic behavior (helping others without repayment) is a
human behavioral trait that is relatively uncommon in other
species, especially in cases like the adoption of an unrelated
orphaned child. Raising an unrelated child takes a large amount
of time and material resources that are hence not available to the
,raising of a biological offspring, so you might expect these
behaviors to be selected against if they had a heritable basis.
Evolutionary psychology nevertheless has tried to explain
altruistic behavior in humans as an adaptation, in other words as
a direct result of natural selection.
IF the hypothesis is correct that adoption of unrelated children
IS a human behavior that evolved as a result of natural selection,
which of the following scenarios would be consistent with this
explanation?
Select one:
a. Humans that lack the strong emotional feeling of empathy that
causes them to want to protect children (in Correct Answers b.
Humans that lack the strong emotional feeling of empathy that
causes them to want to protect children (including unrelated
ones) are more likely to lose biological offspring to accidents or
mishaps as well.
Claytonia virginica is a woodland spring herb with flowers that
vary from white to pale pink to bright pink. This plant is
primarily pollinated by a bee that prefers pink flowers to white
flowers. As a result, Claytonia with pink flowers have greater
relative fruit set than Claytonia with white flowers due to greater
pollination rates. Nevertheless, the percentage of different
flower colors remains stable in the study population from year to
year. Which of these statements might explain this observation?
Select one:
a. Reproductive success is not a good measure for fitness in this
species.
, b. Flower color is not heritable but is instead determined by the
pH of the soil.
c. Fitness is primarily determined by fruit set in this species.
d. The white flowers have evolved pollinator resistance. Correct
Answers b. Flower color is not heritable but is instead
determined by the pH of the soil.
Did the allele frequencies change from the original population in
Question 8 to your predicted offspring generation in Question 9?
Select one:
a. Yes
b. No Correct Answers b. No
IF your hypothesis in the previous question is correct, what else
can you predict as being likely true and might be able to explain
why the behavioral trait "strong empathy for an urge to protect
children" is so common in humans and not other species?
Select one:
a. Altruistic behavior cannot be a heritable trait in most other
species.
b. Most other species are not as smart as humans.
c. Altruistic behavior cannot be a heritable trait in humans.
d. Human babies are more vulnerable and in greater need of
parental care than in most other species.
e. Most other species are not capable of feeling empathy.
Correct Answers d. Human babies are more vulnerable and in
greater need of parental care than in most other species.
