MCAT Practice Questions & Answers
Which of the following neurotransmitters is associated Dopamine (Schizophrenia is associated with high levels of dopamine, or high
with both schizophrenia and Parkinson's disease? sensitivity to dopamine. Parkinson's disease is associated with destruction of the
■GABA dopaminergic neurons in the basal ganglia.)
■Serotonin
■Dopamine
■Enkephalins
Primary groups differ from secondary groups in that: C (Primary groups have direct and close bonds between members, providing
■A) primary groups are shorter-lived than secondary warm, personal, and intimate relationships to its members. Secondary groups,
groups. in contrast, form superficial bonds and tend to last for a shorter period of time.)
■B) primary groups are larger than secondary groups.
■C) primary groups are formed of stronger bonds than
secondary groups.
■D) primary groups are assigned while secondary
groups are chosen.
A student is volunteering in a hospital with a stroke Base rate fallacy (The base rate fallacy occurs when prototypical or
center. When asked what he believes is the prevalence stereotypical factors are used for analysis rather than actual data. Because the
of stroke among those greater than 65 years old, the student is volunteering in a hospital with a stroke center, he sees more patients
student states that it is probably about 40% even who have experienced a stroke than would be expected in a hospital without a
though data analysis indicates that it is significantly stroke center. Thus, this experience changes his perception and results in base
lower. What accounts for this error? rate fallacy. Deductive reasoning, choice (A), refers to drawing conclusions by
■Deductive reasoning integrating different pieces of evidence. The representativeness heuristic,
■Representativeness heuristic choice (B), involves categorization and classification based on how well an
■Base rate fallacy individual example fits its category. Confirmation bias, choice (D), occurs when
■Confirmation bias a person only seeks information that reinforces his or her opinions.)
Why are triacylglycerols used in the human body for C (Triacylglycerols are highly hydrophobic and therefore not highly hydrated
energy storage? (which would add extra weight from the water of hydration, taking away from
■A) They are highly hydrated, and therefore can store the energy density of these molecules), eliminating choice (A). The fatty acid
lots of energy. chains produce twice as much energy as polysaccharides during oxidation
■B) They always have short fatty acid chains, for easy because they are highly reduced. The fatty acid chains vary in length and
access by metabolic enzymes. saturation.)
■C) The carbon atoms of the fatty acid chains are highly
reduced, and therefore yield more energy upon
oxidation.
■D) Polysaccharides, which would actually be a better
energy storage form, would dissolve in the body.
Prolonged vitamin B12 deficiency can be associated Kinesthetic sense (Kinesthetic sense, or proprioception, refers to the ability to
with subacute combined degeneration of the spinal tell where body parts are in three-dimensional space. The sensors for
cord. Patients with this disease have difficulty walking proprioception are found predominantly in the muscles and joints. Loss of
because they lose the ability to feel where their feet are vestibular sense, choice (A), would also cause difficulty walking, but this would
in space. This represents a loss of: be due to a sense of dizziness or vertigo, not an inability to feel one's feet.)
■vestibular sense.
■kinesthetic sense.
■parallel processing.
■feature detection.
, MCAT Practice Questions & Answers
Which of the following is/are function(s) of NADPH in B (NADPH has three primary functions: involvement in biosynthesis of lipids
the cell? and cholesterol (the precursor to steroid hormones), production of
bactericidal bleach in the lysosomes of certain white blood cells, and
►I. Antimicrobial resistance via bacterial destruction by maintenance of a supply of reduced glutathione for protection against free
bleach within lysosomes. radical damage. Energy carriage is an important function of NADH, not
►II. Involvement in the production of the precursors to NADPH.)
steroid hormones.
►III. Functional carriage of energy across organelle
membranes for use within the mitochondria
A) I only
B) I and II only
C) II and III only
D) I, II, and III
Increases in which of the following hormones causes Melatonin (As light diminishes throughout the day, the pineal gland increases
sleepiness? secretion of melatonin, resulting in sleepiness. Cortisol levels, choice (A),
■Cortisol increase throughout the early morning, resulting in wakefulness. Growth
■Growth hormone hormone secretion, choice (B), peaks during slow-wave sleep. Oxytocin,
■Melatonin choice (D), is associated with uterine contractions in childbirth, milk letdown,
■Oxytocin and bonding behavior.)
How does the inner mitochondrial membrane differ B (The outer mitochondrial membrane is very permeable while the inner
from the outer mitochondrial membrane? membrane is highly impermeable. The inner mitochondrial membrane is unique
A) The inner mitochondrial membrane is more within the cell because it lacks cholesterol.)
permeable and lacks cholesterol.
B) The inner mitochondrial membrane is less permeable
and lacks cholesterol.
C) The inner mitochondrial membrane is more
permeable and has cholesterol.
D) The inner mitochondrial membrane is less permeable
and has cholesterol.
Some cellular membranes sequester hydrogen ions on A (A change in pH has a direct correlation to the hydrogen ion (H)
one side in order to create an acidic or basic concentration. Decreasing the pH increases the H+ concentration, which means
environment. For example, the membrane of lysosomes the concentration of products has increased in the oxidation of sulfur dioxide.
contains proton pumps that move hydrogen ions into This means it would be harder to liberate electrons, thus decreasing the emf.
the lysosome. For a cell with the following half- One could also view this decrease in oxidation potential as an increase in
reactions: reduction potential.
If E°red,anode increases, then E°cell must decrease according to
Anode: SO2 + 2 H2O → SO4^2- + 4 H^+ + 2e^- E°cell = Ered,cathode - E°red,anode)
Cathode: Pd^2+ + 2e^- → Pd
How would decreasing the pH of the solution inside the
cell affect the electromotive force (emf)?
A) The emf would decrease.
B) The emf would remain the same.
C) The emf would increase.
D) The emf would become zero.
Which of the following neurotransmitters is associated Dopamine (Schizophrenia is associated with high levels of dopamine, or high
with both schizophrenia and Parkinson's disease? sensitivity to dopamine. Parkinson's disease is associated with destruction of the
■GABA dopaminergic neurons in the basal ganglia.)
■Serotonin
■Dopamine
■Enkephalins
Primary groups differ from secondary groups in that: C (Primary groups have direct and close bonds between members, providing
■A) primary groups are shorter-lived than secondary warm, personal, and intimate relationships to its members. Secondary groups,
groups. in contrast, form superficial bonds and tend to last for a shorter period of time.)
■B) primary groups are larger than secondary groups.
■C) primary groups are formed of stronger bonds than
secondary groups.
■D) primary groups are assigned while secondary
groups are chosen.
A student is volunteering in a hospital with a stroke Base rate fallacy (The base rate fallacy occurs when prototypical or
center. When asked what he believes is the prevalence stereotypical factors are used for analysis rather than actual data. Because the
of stroke among those greater than 65 years old, the student is volunteering in a hospital with a stroke center, he sees more patients
student states that it is probably about 40% even who have experienced a stroke than would be expected in a hospital without a
though data analysis indicates that it is significantly stroke center. Thus, this experience changes his perception and results in base
lower. What accounts for this error? rate fallacy. Deductive reasoning, choice (A), refers to drawing conclusions by
■Deductive reasoning integrating different pieces of evidence. The representativeness heuristic,
■Representativeness heuristic choice (B), involves categorization and classification based on how well an
■Base rate fallacy individual example fits its category. Confirmation bias, choice (D), occurs when
■Confirmation bias a person only seeks information that reinforces his or her opinions.)
Why are triacylglycerols used in the human body for C (Triacylglycerols are highly hydrophobic and therefore not highly hydrated
energy storage? (which would add extra weight from the water of hydration, taking away from
■A) They are highly hydrated, and therefore can store the energy density of these molecules), eliminating choice (A). The fatty acid
lots of energy. chains produce twice as much energy as polysaccharides during oxidation
■B) They always have short fatty acid chains, for easy because they are highly reduced. The fatty acid chains vary in length and
access by metabolic enzymes. saturation.)
■C) The carbon atoms of the fatty acid chains are highly
reduced, and therefore yield more energy upon
oxidation.
■D) Polysaccharides, which would actually be a better
energy storage form, would dissolve in the body.
Prolonged vitamin B12 deficiency can be associated Kinesthetic sense (Kinesthetic sense, or proprioception, refers to the ability to
with subacute combined degeneration of the spinal tell where body parts are in three-dimensional space. The sensors for
cord. Patients with this disease have difficulty walking proprioception are found predominantly in the muscles and joints. Loss of
because they lose the ability to feel where their feet are vestibular sense, choice (A), would also cause difficulty walking, but this would
in space. This represents a loss of: be due to a sense of dizziness or vertigo, not an inability to feel one's feet.)
■vestibular sense.
■kinesthetic sense.
■parallel processing.
■feature detection.
, MCAT Practice Questions & Answers
Which of the following is/are function(s) of NADPH in B (NADPH has three primary functions: involvement in biosynthesis of lipids
the cell? and cholesterol (the precursor to steroid hormones), production of
bactericidal bleach in the lysosomes of certain white blood cells, and
►I. Antimicrobial resistance via bacterial destruction by maintenance of a supply of reduced glutathione for protection against free
bleach within lysosomes. radical damage. Energy carriage is an important function of NADH, not
►II. Involvement in the production of the precursors to NADPH.)
steroid hormones.
►III. Functional carriage of energy across organelle
membranes for use within the mitochondria
A) I only
B) I and II only
C) II and III only
D) I, II, and III
Increases in which of the following hormones causes Melatonin (As light diminishes throughout the day, the pineal gland increases
sleepiness? secretion of melatonin, resulting in sleepiness. Cortisol levels, choice (A),
■Cortisol increase throughout the early morning, resulting in wakefulness. Growth
■Growth hormone hormone secretion, choice (B), peaks during slow-wave sleep. Oxytocin,
■Melatonin choice (D), is associated with uterine contractions in childbirth, milk letdown,
■Oxytocin and bonding behavior.)
How does the inner mitochondrial membrane differ B (The outer mitochondrial membrane is very permeable while the inner
from the outer mitochondrial membrane? membrane is highly impermeable. The inner mitochondrial membrane is unique
A) The inner mitochondrial membrane is more within the cell because it lacks cholesterol.)
permeable and lacks cholesterol.
B) The inner mitochondrial membrane is less permeable
and lacks cholesterol.
C) The inner mitochondrial membrane is more
permeable and has cholesterol.
D) The inner mitochondrial membrane is less permeable
and has cholesterol.
Some cellular membranes sequester hydrogen ions on A (A change in pH has a direct correlation to the hydrogen ion (H)
one side in order to create an acidic or basic concentration. Decreasing the pH increases the H+ concentration, which means
environment. For example, the membrane of lysosomes the concentration of products has increased in the oxidation of sulfur dioxide.
contains proton pumps that move hydrogen ions into This means it would be harder to liberate electrons, thus decreasing the emf.
the lysosome. For a cell with the following half- One could also view this decrease in oxidation potential as an increase in
reactions: reduction potential.
If E°red,anode increases, then E°cell must decrease according to
Anode: SO2 + 2 H2O → SO4^2- + 4 H^+ + 2e^- E°cell = Ered,cathode - E°red,anode)
Cathode: Pd^2+ + 2e^- → Pd
How would decreasing the pH of the solution inside the
cell affect the electromotive force (emf)?
A) The emf would decrease.
B) The emf would remain the same.
C) The emf would increase.
D) The emf would become zero.
