AP Bio - Practice Exam 2 MCQ
Questions and Answers16
Which of the following best explains how the expression of a eukaryotic gene encoding a
protein will differ if the gene is expressed in a prokaryotic cell instead of in a eukaryotic cell? -
ANSWERS -The protein will be made but will not function because prokaryotes cannot remove
introns
Low concentrations of cadmium in the water negatively affect steelhead trout. In a river
community, steelhead trout are part of the trophic structure shown in Figure 1.
Which of the following is the most likely immediate effect of an increase in runoff containing
cadmium on the trophic structure of the river community? - ANSWERS -There will be a large
decrease in the trout population, resulting in an increase in damselfly nymphs
Poaching is the illegal hunting or capturing of wild animals. Both male and female African
elephants have tusks that are a significant source of ivory used for ornaments and jewelry.
Assuming that the size of the tusks is heritable, which of the following is the most likely long-
term effect of poachers targeting African elephants with large tusks? - ANSWERS -A decrease in
average tusk size because the elephants with large tusks are less likely to survive to reproduce
A scientist adds a chemical to a culture of dividing cells in order to disrupt DNA replication. The
replicated DNA produced by the cells is double-stranded, but sections of it lack covalent bonds
between adjacent nucleotides.
Which of the following claims is best supported by the data? - ANSWERS -The chemical inhibits
DNA ligase
,Which of the following best describes the hydrolysis of carbohydrates? - ANSWERS -The
addition of a water molecule breaks a covalent bone between sugar monomers
Which of the following best describes a characteristic of DNA that makes it useful as hereditary
material? - ANSWERS -Nucleotide bases in one strand can only be paired with specific bases in
the other strand
Based on the pedigrees in Figure 1, which of the following best explains the observed pattern of
inheritance? - ANSWERS -The trait is an autosomal recessive, because the cross between
individuals I-1 and I-2 produced an affected offspring
Which of the following best describes the process by which the bacteria are breaking down the
glucose to produce lactic acid? - ANSWERS -The bacteria are breaking down sugars in the
absence of oxygen
Which of the following was the dependent variable in the researcher's experiment? - ANSWERS
-pH
Based on the data in Table 1, which of the following is the earliest time point at which there is a
statistical difference in average pH between the control and the treatment group? - ANSWERS -
35 minutes
According to the data, which of the following best explains the results of the experiment? -
ANSWERS -The pH of the treatment culture was lower than the pH of the control because the
chemical increased the bacterial metabolic rate
A mutation in the gene coding for a single-polypeptide enzyme results in the substitution of
amino acid serine, which has a polar R group, by the amino acid phenylalanine, which has a non
polar R group. When researchers test the catalysis of the normal enzyme and the mutated
enzyme, they find that the mutated enzyme has much lower activity than the normal enzyme
does.
, Which of the following most likely explains how the amino acid substitution has resulted in
decreased catalytic activist by the mutated enzyme? - ANSWERS -The substitution altered the
secondary and tertiary structure of the enzyme so that the mutated enzyme folds into a
different shape than the normal enzyme does
Pitcher plants are carnivorous plants that grow in areas where the soil contains low levels of key
nutrient such as nitrogen. To obtain these nutrients, most pitcher plants capture prey using
traps containing a digestive fluid. The captured prey are then broken down and digested, and
the pitcher plant absorbs the nutrients.
The traps of one species of pitcher plant, Nepenthes hemsleyana, do not contain digestive fluid.
Instead the provide a suitable place for wooly bats (Kerivoula hardwicki) to sleep. The feces
from the bat are released into the trap where nutrients in the feces are absorbed and provide
the plant with the nitrogen it needs.
Which of the following best describes the relationship between the pitcher plant and the wooly
bat? - ANSWERS -The relationship is mutualistic because both the plant and the bat benefit
A particular genetic disorder is associated with a single gene with two alleles. Individuals with
two recessive alleles are affected. The prevalence of the disorder is 1 in 6,600.
Assuming the population is in Hardy-Weinberg equilibrium, which of the following is closest to
the frequency of carriers in the general population? - ANSWERS -0.02430
Blood vessels are surrounded by called smooth muscle cells. Nitric oxide triggers a signaling
cascade in smooth muscle cells that causes the cells to relax.
Which of the following is represented by the gradual increase in thickness of the arrows from
the top to the bottom of Figure 1? - ANSWERS -The number of signaling molecules that are
produced or activated increases with each step in the pathway
Questions and Answers16
Which of the following best explains how the expression of a eukaryotic gene encoding a
protein will differ if the gene is expressed in a prokaryotic cell instead of in a eukaryotic cell? -
ANSWERS -The protein will be made but will not function because prokaryotes cannot remove
introns
Low concentrations of cadmium in the water negatively affect steelhead trout. In a river
community, steelhead trout are part of the trophic structure shown in Figure 1.
Which of the following is the most likely immediate effect of an increase in runoff containing
cadmium on the trophic structure of the river community? - ANSWERS -There will be a large
decrease in the trout population, resulting in an increase in damselfly nymphs
Poaching is the illegal hunting or capturing of wild animals. Both male and female African
elephants have tusks that are a significant source of ivory used for ornaments and jewelry.
Assuming that the size of the tusks is heritable, which of the following is the most likely long-
term effect of poachers targeting African elephants with large tusks? - ANSWERS -A decrease in
average tusk size because the elephants with large tusks are less likely to survive to reproduce
A scientist adds a chemical to a culture of dividing cells in order to disrupt DNA replication. The
replicated DNA produced by the cells is double-stranded, but sections of it lack covalent bonds
between adjacent nucleotides.
Which of the following claims is best supported by the data? - ANSWERS -The chemical inhibits
DNA ligase
,Which of the following best describes the hydrolysis of carbohydrates? - ANSWERS -The
addition of a water molecule breaks a covalent bone between sugar monomers
Which of the following best describes a characteristic of DNA that makes it useful as hereditary
material? - ANSWERS -Nucleotide bases in one strand can only be paired with specific bases in
the other strand
Based on the pedigrees in Figure 1, which of the following best explains the observed pattern of
inheritance? - ANSWERS -The trait is an autosomal recessive, because the cross between
individuals I-1 and I-2 produced an affected offspring
Which of the following best describes the process by which the bacteria are breaking down the
glucose to produce lactic acid? - ANSWERS -The bacteria are breaking down sugars in the
absence of oxygen
Which of the following was the dependent variable in the researcher's experiment? - ANSWERS
-pH
Based on the data in Table 1, which of the following is the earliest time point at which there is a
statistical difference in average pH between the control and the treatment group? - ANSWERS -
35 minutes
According to the data, which of the following best explains the results of the experiment? -
ANSWERS -The pH of the treatment culture was lower than the pH of the control because the
chemical increased the bacterial metabolic rate
A mutation in the gene coding for a single-polypeptide enzyme results in the substitution of
amino acid serine, which has a polar R group, by the amino acid phenylalanine, which has a non
polar R group. When researchers test the catalysis of the normal enzyme and the mutated
enzyme, they find that the mutated enzyme has much lower activity than the normal enzyme
does.
, Which of the following most likely explains how the amino acid substitution has resulted in
decreased catalytic activist by the mutated enzyme? - ANSWERS -The substitution altered the
secondary and tertiary structure of the enzyme so that the mutated enzyme folds into a
different shape than the normal enzyme does
Pitcher plants are carnivorous plants that grow in areas where the soil contains low levels of key
nutrient such as nitrogen. To obtain these nutrients, most pitcher plants capture prey using
traps containing a digestive fluid. The captured prey are then broken down and digested, and
the pitcher plant absorbs the nutrients.
The traps of one species of pitcher plant, Nepenthes hemsleyana, do not contain digestive fluid.
Instead the provide a suitable place for wooly bats (Kerivoula hardwicki) to sleep. The feces
from the bat are released into the trap where nutrients in the feces are absorbed and provide
the plant with the nitrogen it needs.
Which of the following best describes the relationship between the pitcher plant and the wooly
bat? - ANSWERS -The relationship is mutualistic because both the plant and the bat benefit
A particular genetic disorder is associated with a single gene with two alleles. Individuals with
two recessive alleles are affected. The prevalence of the disorder is 1 in 6,600.
Assuming the population is in Hardy-Weinberg equilibrium, which of the following is closest to
the frequency of carriers in the general population? - ANSWERS -0.02430
Blood vessels are surrounded by called smooth muscle cells. Nitric oxide triggers a signaling
cascade in smooth muscle cells that causes the cells to relax.
Which of the following is represented by the gradual increase in thickness of the arrows from
the top to the bottom of Figure 1? - ANSWERS -The number of signaling molecules that are
produced or activated increases with each step in the pathway
