MCAT Practice Questions
MCAT Practice Questions
Study online at https://quizlet.com/_2dbdxt
1. Why are triacylglycerols used in the hu- C
man body for energy storage?
Triacylglycerols are highly hydrophobic and
A) They are highly hydrated, and there- therefore not highly hydrated (which would add
fore can store lots of energy. extra weight from the water of hydration, tak-
B) They always have short fatty acid ing away from the energy density of these mol-
chains, for easy access by metabolic en- ecules), eliminating choice (A). The fatty acid
zymes. chains produce twice as much energy as polysac-
C) The carbon atoms of the fatty acid charides during oxidation because they are high-
chains are highly reduced, and there- ly reduced. The fatty acid chains vary in length
fore yield more energy upon oxidation. and saturation.
D) Polysaccharides, which would actu-
ally be a better energy storage form,
would dissolve in the body.
2. Action potentials travel down neural ax- A
ons that resist the flow of current. In This question tests your knowledge of resistance
considering a theoretical circuit, one in wires. An electrical wire's resistance is directly
normally assumes that the wire has no proportional to its length and inversely propor-
resistivity. In the real world, however, tional to its cross-sectional area. Think of it as
wire resistivity is an important consider- gravel in a pipe—the wider the pipe and the
ation. Which of the following is a way to shorter the pipe, the easier it is for water to go
increase resistance? through it.
A) Lengthen the wire B is incorrect because when a wire's cross-sec-
B) Widen the wire tional area is increased, its resistivity is de-
C) Lower the temperature creased.
D) Change from tungsten to copper
wire C is incorrect because lowering temperature de-
creases resistivity. Think superconductors.
D is incorrect because tungsten has higher resis-
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, MCAT Practice Questions
MCAT Practice Questions
Study online at https://quizlet.com/_2dbdxt
tivity than copper. Tungsten is used for lightbulb
filaments because of its higher resistivity.
3. Sexually reproducing species have a se- B
lective advantage over asexually repro- The reason those species that reproduce sex-
ducing species, because sexual repro- ually have a selective advantage is because
duction: gene recombination is a given with every fer-
tilization—two genetically unique nuclei—the
A) is more energy efficient. sperm nucleus and the egg nucleus--fuse to
B) creates novel genetic recombina- form an equally genetically unique zygote. This is
tions. the main means of introducing phenotypic vari-
C) decreases the likelihood of muta- ability into a population.
tions.
D) always decreases offspring survival
rate.
4. Pus is primarily composed of phagocy- B
tosed bacterial remnants. Which of the Phagocytosis plays an important role in both
following would you expect to find in a the nonspecific and humoral response to foreign
microscopic sample of pus? pathogens. At the level of the skin, macrophages
dwell in the connective tissue surrounding the
A) Red blood cells, white blood cells, and organs of the body. Neutrophils are recruited to
platelets the site of entry and become part of the non-spe-
B) Granulocytes, monocytes, and cific response to invading bacteria, working in
macrophages combination with monocytes and macrophages
C) Eosinophils, basophils, and neu- to completely decompose bacteria. The cell-me-
trophils diated branch of the immune system does not
D) Collagen, white blood cells, and calci- result in pus formation.
um
5. Which of the following is true about B
cholesterol? Cholesterol is a steroid precursor that has vari-
able effects on membrane fluidity depending
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MCAT Practice Questions
Study online at https://quizlet.com/_2dbdxt
1. Why are triacylglycerols used in the hu- C
man body for energy storage?
Triacylglycerols are highly hydrophobic and
A) They are highly hydrated, and there- therefore not highly hydrated (which would add
fore can store lots of energy. extra weight from the water of hydration, tak-
B) They always have short fatty acid ing away from the energy density of these mol-
chains, for easy access by metabolic en- ecules), eliminating choice (A). The fatty acid
zymes. chains produce twice as much energy as polysac-
C) The carbon atoms of the fatty acid charides during oxidation because they are high-
chains are highly reduced, and there- ly reduced. The fatty acid chains vary in length
fore yield more energy upon oxidation. and saturation.
D) Polysaccharides, which would actu-
ally be a better energy storage form,
would dissolve in the body.
2. Action potentials travel down neural ax- A
ons that resist the flow of current. In This question tests your knowledge of resistance
considering a theoretical circuit, one in wires. An electrical wire's resistance is directly
normally assumes that the wire has no proportional to its length and inversely propor-
resistivity. In the real world, however, tional to its cross-sectional area. Think of it as
wire resistivity is an important consider- gravel in a pipe—the wider the pipe and the
ation. Which of the following is a way to shorter the pipe, the easier it is for water to go
increase resistance? through it.
A) Lengthen the wire B is incorrect because when a wire's cross-sec-
B) Widen the wire tional area is increased, its resistivity is de-
C) Lower the temperature creased.
D) Change from tungsten to copper
wire C is incorrect because lowering temperature de-
creases resistivity. Think superconductors.
D is incorrect because tungsten has higher resis-
www.stuvia.com
1/6
, MCAT Practice Questions
MCAT Practice Questions
Study online at https://quizlet.com/_2dbdxt
tivity than copper. Tungsten is used for lightbulb
filaments because of its higher resistivity.
3. Sexually reproducing species have a se- B
lective advantage over asexually repro- The reason those species that reproduce sex-
ducing species, because sexual repro- ually have a selective advantage is because
duction: gene recombination is a given with every fer-
tilization—two genetically unique nuclei—the
A) is more energy efficient. sperm nucleus and the egg nucleus--fuse to
B) creates novel genetic recombina- form an equally genetically unique zygote. This is
tions. the main means of introducing phenotypic vari-
C) decreases the likelihood of muta- ability into a population.
tions.
D) always decreases offspring survival
rate.
4. Pus is primarily composed of phagocy- B
tosed bacterial remnants. Which of the Phagocytosis plays an important role in both
following would you expect to find in a the nonspecific and humoral response to foreign
microscopic sample of pus? pathogens. At the level of the skin, macrophages
dwell in the connective tissue surrounding the
A) Red blood cells, white blood cells, and organs of the body. Neutrophils are recruited to
platelets the site of entry and become part of the non-spe-
B) Granulocytes, monocytes, and cific response to invading bacteria, working in
macrophages combination with monocytes and macrophages
C) Eosinophils, basophils, and neu- to completely decompose bacteria. The cell-me-
trophils diated branch of the immune system does not
D) Collagen, white blood cells, and calci- result in pus formation.
um
5. Which of the following is true about B
cholesterol? Cholesterol is a steroid precursor that has vari-
able effects on membrane fluidity depending
www.stuvia.com
2/6
