MCAT Practice Verified Exams Q&As, Top
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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. -
Correct Answers ✅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.
Action potentials travel down neural axons that resist the
flow of current. In considering a theoretical circuit, one
normally assumes that the wire has no resistivity. In the
real world, however, wire resistivity is an important
, MCAT Practice Verified Exams Q&As, Top
Grade Assurance 2026
consideration. Which of the following is a way to increase
resistance?
A) Lengthen the wire
B) Widen the wire
C) Lower the temperature
D) Change from tungsten to copper wire - Correct
Answers ✅A
This question tests your knowledge of resistance in wires.
An electrical wire's resistance is directly proportional to
its length and inversely proportional to its cross-sectional
area. Think of it as gravel in a pipe—the wider the pipe
and the shorter the pipe, the easier it is for water to go
through it.
B is incorrect because when a wire's cross-sectional area
is increased, its resistivity is decreased.
C is incorrect because lowering temperature decreases
resistivity. Think superconductors.
D is incorrect because tungsten has higher resistivity
than copper. Tungsten is used for lightbulb filaments
because of its higher resistivity.
Grade Assurance 2026
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. -
Correct Answers ✅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.
Action potentials travel down neural axons that resist the
flow of current. In considering a theoretical circuit, one
normally assumes that the wire has no resistivity. In the
real world, however, wire resistivity is an important
, MCAT Practice Verified Exams Q&As, Top
Grade Assurance 2026
consideration. Which of the following is a way to increase
resistance?
A) Lengthen the wire
B) Widen the wire
C) Lower the temperature
D) Change from tungsten to copper wire - Correct
Answers ✅A
This question tests your knowledge of resistance in wires.
An electrical wire's resistance is directly proportional to
its length and inversely proportional to its cross-sectional
area. Think of it as gravel in a pipe—the wider the pipe
and the shorter the pipe, the easier it is for water to go
through it.
B is incorrect because when a wire's cross-sectional area
is increased, its resistivity is decreased.
C is incorrect because lowering temperature decreases
resistivity. Think superconductors.
D is incorrect because tungsten has higher resistivity
than copper. Tungsten is used for lightbulb filaments
because of its higher resistivity.
