MCAT AAMC Practice Exam 3 Questions and
Answers
Question 1
Which critique of laboratory research on memory for emotional events is concerned
with generalizability?
A. Potential confounding variables are not always controlled in laboratory studies.
B. Retention tests employed in laboratory studies are usually concerned with factual
information rather than emotions.
C. The intensity of emotional responses is more accurately measured after the event
in laboratory studies.
D. Memories and emotional experiences in real life are very different from those
generated in laboratory studies.
Correct Answer
D.
This is a Psychology question that falls under the content category "Making sense of
the environment." The answer to this question is D because generalizability refers to
external validity, which is the extent to which the results of a scientific investigation
would generalize to other settings and populations. It is dependent on the extent to
which the processes studied in the investigation represent the processes presumed
to be operating outside the laboratory. It is a Scientific Reasoning and Problem
Solving question because the question involves reasoning about the relationship
between psychological phenomena as they normally occur and findings from
laboratory research.
Page 1 of 48
,Question 2
Which statement best accounts for the hereditary transmission of SDH-linked
paraganglioma in a parent specific manner? SDH is:
A. an imprinted gene.
B. a Y-linked gene.
C. an X-linked gene.
D. a tumor suppressor gene.
Correct Answer
A.
This is a Biology question that falls under the content category "Transmission of
genetic information from the gene to the protein." The answer to this question is A
because imprinted genes are expressed in a parent-specific manner. B is incorrect
because based on the passage both sexes may carry the mutated allele. It is a
Knowledge of Scientific Concepts and Principles question because it requires
knowledge of regulation of gene expression.
Question 3
A researcher criticizes the methods used in the study, stating that teachers' ratings
may not be a valid way of assessing the students' emotional problems. Which
hypothetical finding is most likely to reduce this concern?
A. A positive correlation between the number of emotional problems observed in
students and the number of classmates reading below grade level
B. A negative correlation between the number of emotional problems observed in
students and the number of disruptions experienced by the teacher per day
C. A positive correlation between the teachers' ratings of the number of emotional
problems observed in students and the parents' rating of the same variable
D. A negative correlation between the teachers' ratings of the number of emotional
problems observed in students at two different times
Correct Answer
C.
This is a Psychology question that falls under the content category "Responding to
the world." The answer to this question is C because when two independent
measures of the same variable converge, it supports the validity of both measures. It
is a Reasoning about the Design and Execution of Research question because the
question involves determining how additional information can be used to judge the
validity of specific measures of the variables (teachers' ratings of children's
behavioral and emotional problems).
Page 2 of 48
,Question 4
Radioactive tritium (3H) labeled guanine has been used to measure the rate of
biochemical processes that involve its binding or incorporation. Given that water is
the solvent for this type of experiment, what is the best site for tritium labeling?
A. I
B. II
C. III
D. IV
Correct Answer
A.
This is an Organic Chemistry question that falls under the content category
"Structure, function, and reactivity of biologically-relevant molecules." The answer to
this question is A, because the best site for tritium labeling would not exchange the
tritium ions for protons in water. All of the N−H sites (II−IV) would readily exchange
tritium protons due to their lone pair-facilitating protonation and subsequent
tritium exchange with water, but the C−H site (I), lacking a lone pair, would retain its
tritium label. It is a Reasoning about the Design and Execution of Research question
because the selection of the tritium-labeling site under aqueous conditions is
essential to the experimental design.
Page 3 of 48
, Question 5
When two amino acids are joined via a peptide bond, what is the mass of the
byproduct of this reaction? (Note: Assume that the amino acids were not modified by
protecting groups.)
A. 17 amu
B. 18 amu
C. 32 amu
D. 44 amu
Correct Answer
B.
This is an Organic Chemistry question that falls under the content category
"Structure, function, and reactivity of biologically-relevant molecules." The answer to
this question is B because the formation of a peptide bond is accompanied by the
formation of water as a by-product, and the mass of water is 18 amu. It is a
Scientific Reasoning and Problem Solving question because one must understand
(1) that water is released as a by-product of peptide bond formation from the OH of
the carboxyl group and the NH of the amino group, and (2) that the mass of H2O is
the sum of its atomic masses.
Question 6
HDACs change chromatin by:
A. decreasing its coiling and promoting DNA replication.
B. increasing its condensation and inhibiting transcription.
C. decreasing charge repulsion between acetyl groups, which increases transcription.
D. loosening the attachment of DNA to nucleosome core particles.
Correct Answer
B.
This is a Biology question that falls under the content category "Transmission of
genetic information from the gene to the protein." The answer to this question is B
because the passage states that HDACs counter the effects of histone
acetyltransferases (HATs). As histone acetylation typically promotes transcription by
modifying chromatin structure, HDACs would inhibit transcription by condensing
chromatin structure. It is a Knowledge of Scientific Concepts and Principles question
because it requires knowledge of how transcription can be altered by histone and
chromatin modification.
Page 4 of 48
Answers
Question 1
Which critique of laboratory research on memory for emotional events is concerned
with generalizability?
A. Potential confounding variables are not always controlled in laboratory studies.
B. Retention tests employed in laboratory studies are usually concerned with factual
information rather than emotions.
C. The intensity of emotional responses is more accurately measured after the event
in laboratory studies.
D. Memories and emotional experiences in real life are very different from those
generated in laboratory studies.
Correct Answer
D.
This is a Psychology question that falls under the content category "Making sense of
the environment." The answer to this question is D because generalizability refers to
external validity, which is the extent to which the results of a scientific investigation
would generalize to other settings and populations. It is dependent on the extent to
which the processes studied in the investigation represent the processes presumed
to be operating outside the laboratory. It is a Scientific Reasoning and Problem
Solving question because the question involves reasoning about the relationship
between psychological phenomena as they normally occur and findings from
laboratory research.
Page 1 of 48
,Question 2
Which statement best accounts for the hereditary transmission of SDH-linked
paraganglioma in a parent specific manner? SDH is:
A. an imprinted gene.
B. a Y-linked gene.
C. an X-linked gene.
D. a tumor suppressor gene.
Correct Answer
A.
This is a Biology question that falls under the content category "Transmission of
genetic information from the gene to the protein." The answer to this question is A
because imprinted genes are expressed in a parent-specific manner. B is incorrect
because based on the passage both sexes may carry the mutated allele. It is a
Knowledge of Scientific Concepts and Principles question because it requires
knowledge of regulation of gene expression.
Question 3
A researcher criticizes the methods used in the study, stating that teachers' ratings
may not be a valid way of assessing the students' emotional problems. Which
hypothetical finding is most likely to reduce this concern?
A. A positive correlation between the number of emotional problems observed in
students and the number of classmates reading below grade level
B. A negative correlation between the number of emotional problems observed in
students and the number of disruptions experienced by the teacher per day
C. A positive correlation between the teachers' ratings of the number of emotional
problems observed in students and the parents' rating of the same variable
D. A negative correlation between the teachers' ratings of the number of emotional
problems observed in students at two different times
Correct Answer
C.
This is a Psychology question that falls under the content category "Responding to
the world." The answer to this question is C because when two independent
measures of the same variable converge, it supports the validity of both measures. It
is a Reasoning about the Design and Execution of Research question because the
question involves determining how additional information can be used to judge the
validity of specific measures of the variables (teachers' ratings of children's
behavioral and emotional problems).
Page 2 of 48
,Question 4
Radioactive tritium (3H) labeled guanine has been used to measure the rate of
biochemical processes that involve its binding or incorporation. Given that water is
the solvent for this type of experiment, what is the best site for tritium labeling?
A. I
B. II
C. III
D. IV
Correct Answer
A.
This is an Organic Chemistry question that falls under the content category
"Structure, function, and reactivity of biologically-relevant molecules." The answer to
this question is A, because the best site for tritium labeling would not exchange the
tritium ions for protons in water. All of the N−H sites (II−IV) would readily exchange
tritium protons due to their lone pair-facilitating protonation and subsequent
tritium exchange with water, but the C−H site (I), lacking a lone pair, would retain its
tritium label. It is a Reasoning about the Design and Execution of Research question
because the selection of the tritium-labeling site under aqueous conditions is
essential to the experimental design.
Page 3 of 48
, Question 5
When two amino acids are joined via a peptide bond, what is the mass of the
byproduct of this reaction? (Note: Assume that the amino acids were not modified by
protecting groups.)
A. 17 amu
B. 18 amu
C. 32 amu
D. 44 amu
Correct Answer
B.
This is an Organic Chemistry question that falls under the content category
"Structure, function, and reactivity of biologically-relevant molecules." The answer to
this question is B because the formation of a peptide bond is accompanied by the
formation of water as a by-product, and the mass of water is 18 amu. It is a
Scientific Reasoning and Problem Solving question because one must understand
(1) that water is released as a by-product of peptide bond formation from the OH of
the carboxyl group and the NH of the amino group, and (2) that the mass of H2O is
the sum of its atomic masses.
Question 6
HDACs change chromatin by:
A. decreasing its coiling and promoting DNA replication.
B. increasing its condensation and inhibiting transcription.
C. decreasing charge repulsion between acetyl groups, which increases transcription.
D. loosening the attachment of DNA to nucleosome core particles.
Correct Answer
B.
This is a Biology question that falls under the content category "Transmission of
genetic information from the gene to the protein." The answer to this question is B
because the passage states that HDACs counter the effects of histone
acetyltransferases (HATs). As histone acetylation typically promotes transcription by
modifying chromatin structure, HDACs would inhibit transcription by condensing
chromatin structure. It is a Knowledge of Scientific Concepts and Principles question
because it requires knowledge of how transcription can be altered by histone and
chromatin modification.
Page 4 of 48
