MCAT Practice Questions and
Answers 100% Correct
A stroke patient comprehends speech but cannot move her mouth to form words.
Which of the following brain areas is likely affected?
■Broca's area
■Wernicke's Area
■Arcuate fasciculus
■Superior temporal gyrus - ANSWER - Broca's area (Broca's area governs the motor
function of language. A stroke that affects Broca's area will leave receptive
language intact, but word formation will be affected. A stroke affecting Wernicke's
area, choice (B), will make it so the individual is unable to comprehend speech. A
stroke affecting the arcuate fasciculus, choice (C), will result in an inability to repeat
words heard but spontaneous language production is intact. The superior temporal
gyrus, choice (D), is where Wernicke's area is located.)
Each individual in a group of teenagers is asked to estimate the height of a tree.
One individual estimates the height to be 25 feet, but after discussing with the
group is convinced that the height is likely closer to 40 feet. Which type of
conformity is seen here?
■Obedience
■Identification
■Internalization
■Compliance - ANSWER - Internalization (Internalization refers to the type of
conformity in which an individual changes her outward opinion to match the group
and also personally agrees with those ideas.)
Which of the following neurotransmitters is associated with both schizophrenia and
Parkinson's disease?
■GABA
■Serotonin
■Dopamine
,■Enkephalins - ANSWER - Dopamine (Schizophrenia is associated with high levels of
dopamine, or high sensitivity to dopamine. Parkinson's disease is associated with
destruction of the dopaminergic neurons in the basal ganglia.)
Primary groups differ from secondary groups in that:
■A) primary groups are shorter-lived than secondary groups.
■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. - ANSWER - C
(Primary groups have direct and close bonds between members, providing warm,
personal, and intimate relationships to its members. Secondary groups, in contrast,
form superficial bonds and tend to last for a shorter period of time.)
A student is volunteering in a hospital with a stroke center. When asked what he
believes is the prevalence of stroke among those greater than 65 years old, the
student states that it is probably about 40% even though data analysis indicates
that it is significantly lower. What accounts for this error?
■Deductive reasoning
■Representativeness heuristic
■Base rate fallacy
■Confirmation bias - ANSWER - Base rate fallacy (The base rate fallacy occurs when
prototypical or stereotypical factors are used for analysis rather than actual data.
Because the student is volunteering in a hospital with a stroke center, he sees more
patients who have experienced a stroke than would be expected in a hospital
without a stroke center. Thus, this experience changes his perception and results in
base rate fallacy. Deductive reasoning, choice (A), refers to drawing conclusions by
integrating different pieces of evidence. The representativeness heuristic, choice
(B), involves categorization and classification based on how well an individual
example fits its category. Confirmation bias, choice (D), occurs when a person only
seeks information that reinforces his or her opinions.)
Why are triacylglycerols used in the human body for energy storage?
■A) They are highly hydrated, and therefore can store lots of energy.
■B) They always have short fatty acid chains, for easy access by metabolic
enzymes.
■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. - ANSWER - C (Triacylglycerols are highly hydrophobic and
therefore not highly hydrated (which would add extra weight from the water of
hydration, taking away from the energy density of these molecules), eliminating
choice (A). The fatty acid chains produce twice as much energy as polysaccharides
during oxidation because they are highly reduced. The fatty acid chains vary in
length and saturation.)
Prolonged vitamin B12 deficiency can be associated with subacute combined
degeneration of the spinal cord. Patients with this disease have difficulty walking
because they lose the ability to feel where their feet are in space. This represents a
loss of:
■vestibular sense.
■kinesthetic sense.
■parallel processing.
■feature detection. - ANSWER - Kinesthetic sense (Kinesthetic sense, or
proprioception, refers to the ability to tell where body parts are in three-dimensional
space. The sensors for proprioception are found predominantly in the muscles and
joints. Loss of vestibular sense, choice (A), would also cause difficulty walking, but
this would be due to a sense of dizziness or vertigo, not an inability to feel one's
feet.)
Which of the following is/are function(s) of NADPH in the cell?
►I. Antimicrobial resistance via bacterial destruction by bleach within lysosomes.
►II. Involvement in the production of the precursors to 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 - ANSWER - B (NADPH has three primary functions: involvement in
biosynthesis of lipids and cholesterol (the precursor to steroid hormones),
production of bactericidal bleach in the lysosomes of certain white blood cells, and
maintenance of a supply of reduced glutathione for protection against free radical
damage. Energy carriage is an important function of NADH, not NADPH.)
