AP BIOLOGY MIDTERM EXAM
which of the following principles is NOT part of Darwin's original theory of evolution by natural
selection?
A. Evolution is a gradual process that occurs over long periods of time.
B. Variation occurs among individuals in a population.
C. Mutations are the ultimate source of genetic variation.
D. More individuals are born than will survive.
C
If a population is ini Hardy Weinberg equilibrium then:
A. it is evolving to adapt to environmental changes
B. the frequency of alleles is changing with each generation
C. mutations, immigration, and selective mating are changing allele frequencies
D. it is not evolving and allele frequencies remain the same with each generation
E. Homozygous recessive individuals are less fit.
D
For a population in Hardy-Weinberg equilibrium, the frequency of the recessive allele:
A. increases with each generation until it reaches 50%
B. decreases each generation until it reaches 25%
C. remains the same in every generation.
D. decreases due to negative selection pressure on homozygous recessive individuals.
E. increases due to the occurence of new mutations
C
which of the following is probably the best explanation for the fact that Antarctic penguins cant fly,
although there is evidence that millions of years ago their ancestors could do so?
A. penguins live on land and feed in the water, therefore they have no need to fly
B. the antarctic home of penguins is flat and barren, so there's no place to fly
C. ancestral penguins without large wings were better able to swim and feed in water, so they passed
their genes for shorter wing structure to their offspring
D. ancestral penguins didnt use their wings for long periods of time, so todays penguins have tiny
nonfunctional wings
C
the appearance of a fertile, polyploidy individual within a population of diploid organisms is a possible
source of a new species. if this individual is capable of reproducing to form a new population.
scientists would consider this to be an example of:
A. allopatric speciation
B. sympatric speciation
C. polygenic speciation
D. genetic drift
E. hardy weinberg equilibrium
B
if a population that contains 16% homozygous recessive individuals(blue eyes)and 84% individuals
with brown eyes (homozygous dominant and heterozygotes), what is the frequency of the dominant
allele in the population?
A. 0.6
B. 0.4
C. 0.32
, D. 0.64
E. 0.8
A
what is the only factor that can change allele frequencies in populations to produce adaptive
evolutionary change?
A. mutation
B. gene flow (immigration)
C. non-random mating
D. genetic drift
E. selection
E
in certain native american groups, albinism due to a homozygous recessive condition in the
biochemical pathway for melanin is sometimes seen. if the frequency of the allele for this condition is
0.06, which of the following is closest to the frequency of the dominant allele in this population?
(assume the population is in HW equilibrium)
A. 0.04
B. 0.06
C. 0.16
D. 0.36
E. 0.94
E
How does natural selection affect the frequency of mutations?
A. under conditions of high selection pressure, beneficial mutations occur more frequently.
B. natural selection doesnt affect the frequency of mutations
C. all mutations increase when selection pressure is high
D. when there is no selection pressure, mutations do not occur
E. mutations occur less frequently when selection pressure is high
B
genetic drift is increased by all of the following EXCEPT:
A. small population size
B. bottleneck effects when the population size is greatly reduced, then recovers
C. founder effects when a small number of individuals are isolated and reproduce to form a new sub-
population
D. movement of individuals from one isolated population to another
E. genetic isolation of a small groups within a population
D
IN A CERTAIN FLOCK OF SHEEP, 4% OF THE POPULATION HAS BLACK WOOL AND 96% HAS WHITE
WOOL. ASSUME THE POPULATION IS IN HW EQUILIBRIUM
if black wool is a recessive trait, what percentage of the population is heterozygous for this trait?
A. 4%
B. 20%
C. 32%
D. 64%
E. 80%
C
which of the following principles is NOT part of Darwin's original theory of evolution by natural
selection?
A. Evolution is a gradual process that occurs over long periods of time.
B. Variation occurs among individuals in a population.
C. Mutations are the ultimate source of genetic variation.
D. More individuals are born than will survive.
C
If a population is ini Hardy Weinberg equilibrium then:
A. it is evolving to adapt to environmental changes
B. the frequency of alleles is changing with each generation
C. mutations, immigration, and selective mating are changing allele frequencies
D. it is not evolving and allele frequencies remain the same with each generation
E. Homozygous recessive individuals are less fit.
D
For a population in Hardy-Weinberg equilibrium, the frequency of the recessive allele:
A. increases with each generation until it reaches 50%
B. decreases each generation until it reaches 25%
C. remains the same in every generation.
D. decreases due to negative selection pressure on homozygous recessive individuals.
E. increases due to the occurence of new mutations
C
which of the following is probably the best explanation for the fact that Antarctic penguins cant fly,
although there is evidence that millions of years ago their ancestors could do so?
A. penguins live on land and feed in the water, therefore they have no need to fly
B. the antarctic home of penguins is flat and barren, so there's no place to fly
C. ancestral penguins without large wings were better able to swim and feed in water, so they passed
their genes for shorter wing structure to their offspring
D. ancestral penguins didnt use their wings for long periods of time, so todays penguins have tiny
nonfunctional wings
C
the appearance of a fertile, polyploidy individual within a population of diploid organisms is a possible
source of a new species. if this individual is capable of reproducing to form a new population.
scientists would consider this to be an example of:
A. allopatric speciation
B. sympatric speciation
C. polygenic speciation
D. genetic drift
E. hardy weinberg equilibrium
B
if a population that contains 16% homozygous recessive individuals(blue eyes)and 84% individuals
with brown eyes (homozygous dominant and heterozygotes), what is the frequency of the dominant
allele in the population?
A. 0.6
B. 0.4
C. 0.32
, D. 0.64
E. 0.8
A
what is the only factor that can change allele frequencies in populations to produce adaptive
evolutionary change?
A. mutation
B. gene flow (immigration)
C. non-random mating
D. genetic drift
E. selection
E
in certain native american groups, albinism due to a homozygous recessive condition in the
biochemical pathway for melanin is sometimes seen. if the frequency of the allele for this condition is
0.06, which of the following is closest to the frequency of the dominant allele in this population?
(assume the population is in HW equilibrium)
A. 0.04
B. 0.06
C. 0.16
D. 0.36
E. 0.94
E
How does natural selection affect the frequency of mutations?
A. under conditions of high selection pressure, beneficial mutations occur more frequently.
B. natural selection doesnt affect the frequency of mutations
C. all mutations increase when selection pressure is high
D. when there is no selection pressure, mutations do not occur
E. mutations occur less frequently when selection pressure is high
B
genetic drift is increased by all of the following EXCEPT:
A. small population size
B. bottleneck effects when the population size is greatly reduced, then recovers
C. founder effects when a small number of individuals are isolated and reproduce to form a new sub-
population
D. movement of individuals from one isolated population to another
E. genetic isolation of a small groups within a population
D
IN A CERTAIN FLOCK OF SHEEP, 4% OF THE POPULATION HAS BLACK WOOL AND 96% HAS WHITE
WOOL. ASSUME THE POPULATION IS IN HW EQUILIBRIUM
if black wool is a recessive trait, what percentage of the population is heterozygous for this trait?
A. 4%
B. 20%
C. 32%
D. 64%
E. 80%
C
