HESI A2 Biology practice Exam
Questions and Answers 100% pass
Which of the following is NOT a part of the body's chemical defense system
against infection?
a. Urine
b. Hydrochloric acid
c. Agranulocyte
d. Lysozyme - ANSWER-- Agranulocytes
Agranulocytes are a type of white blood cell and therefore are not a part of the
body's chemical defense system.
Which of the following is considered an example of naturally acquired passive
immunity?
a. Attenuated (live) vaccine injection
b. Breastfeeding
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,c. Inactivated (killed) vaccine injection
d. Exposure to a disease and subsequent immunity - ANSWER-- breastfeeding
Natural passive immunity occurs when live antibodies are transferred from one
individual to another, such as when anti-bodies are transferred from a mother to
her baby via breast milk.
Worms lack which of the following?
a. Eyes and brain
b. Brain
c. Eyes
d. Nerve centers - ANSWER-- eyes and brain
Worms lack both eyes and a brain, but they do have nerve centers.
Which organelle is responsible for generating ATP that is used for chemical
energy?
a. Mitochondria
b. Vesicle
c. Ribosome
d. Golgi apparatus - ANSWER-- mitochondria
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,The mitochondrion is often referred to as the "power plant" of the cell, because it
generates ATP, the cell's source of chemical energy.
Which of the following is true with regard to eukaryotic and prokaryotic cells?
a. Prokaryotic cells can contain lysosomes.
b. Eukaryotic cells have mitochondria.
c. Prokaryotic cells can contain lysosomes and eukaryotic cells have mitochondria.
d. Prokaryotic cells have a nucleus. - ANSWER-- Eukaryotic cells have
mitochondria.
One of the major differences between eukaryotic cells and prokaryotic cells is that
eukaryotic cells contain organelles, such as mitochondria, whereas prokaryotic cells
do not.
Positive feedback is a mechanism used by the body that results in amplification or
enhancement of a signal that has already been activated. An example of this would
be:
a. Slowing metabolism in response to starvation
b. Shivering to increase temperature
c. Blood vessels regulating blood pressure
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, d. The release of oxytocin to increase contractions during childbirth - ANSWER--
The release of oxytocin to increase contractions during childbirth
Contractions in childbirth are considered a positive feedback loop because each
contraction stimulates the brain to release more Oxytocin, which in turn stimulates
more contractions.
When placed in a hypotonic solution, a cell will do which of the following?
a. Remain the same
b. Disintegrate
c. Swell
d. Shrink - ANSWER-- swell
Water always moves from areas of higher concentration to lower concentration. A
hypotonic solution contains less solutes and more water then the contents inside of
the cell, so water will move from outside of the cell to inside, causing it to swell.
Which is NOT an effect of photo-oxidation?
a. Increase in tensile strength
b. Discoloration
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Questions and Answers 100% pass
Which of the following is NOT a part of the body's chemical defense system
against infection?
a. Urine
b. Hydrochloric acid
c. Agranulocyte
d. Lysozyme - ANSWER-- Agranulocytes
Agranulocytes are a type of white blood cell and therefore are not a part of the
body's chemical defense system.
Which of the following is considered an example of naturally acquired passive
immunity?
a. Attenuated (live) vaccine injection
b. Breastfeeding
©️COPYRIGHT 2025, ALL RIGHTS RESERVED. 1
,c. Inactivated (killed) vaccine injection
d. Exposure to a disease and subsequent immunity - ANSWER-- breastfeeding
Natural passive immunity occurs when live antibodies are transferred from one
individual to another, such as when anti-bodies are transferred from a mother to
her baby via breast milk.
Worms lack which of the following?
a. Eyes and brain
b. Brain
c. Eyes
d. Nerve centers - ANSWER-- eyes and brain
Worms lack both eyes and a brain, but they do have nerve centers.
Which organelle is responsible for generating ATP that is used for chemical
energy?
a. Mitochondria
b. Vesicle
c. Ribosome
d. Golgi apparatus - ANSWER-- mitochondria
©️COPYRIGHT 2025, ALL RIGHTS RESERVED. 2
,The mitochondrion is often referred to as the "power plant" of the cell, because it
generates ATP, the cell's source of chemical energy.
Which of the following is true with regard to eukaryotic and prokaryotic cells?
a. Prokaryotic cells can contain lysosomes.
b. Eukaryotic cells have mitochondria.
c. Prokaryotic cells can contain lysosomes and eukaryotic cells have mitochondria.
d. Prokaryotic cells have a nucleus. - ANSWER-- Eukaryotic cells have
mitochondria.
One of the major differences between eukaryotic cells and prokaryotic cells is that
eukaryotic cells contain organelles, such as mitochondria, whereas prokaryotic cells
do not.
Positive feedback is a mechanism used by the body that results in amplification or
enhancement of a signal that has already been activated. An example of this would
be:
a. Slowing metabolism in response to starvation
b. Shivering to increase temperature
c. Blood vessels regulating blood pressure
©️COPYRIGHT 2025, ALL RIGHTS RESERVED. 3
, d. The release of oxytocin to increase contractions during childbirth - ANSWER--
The release of oxytocin to increase contractions during childbirth
Contractions in childbirth are considered a positive feedback loop because each
contraction stimulates the brain to release more Oxytocin, which in turn stimulates
more contractions.
When placed in a hypotonic solution, a cell will do which of the following?
a. Remain the same
b. Disintegrate
c. Swell
d. Shrink - ANSWER-- swell
Water always moves from areas of higher concentration to lower concentration. A
hypotonic solution contains less solutes and more water then the contents inside of
the cell, so water will move from outside of the cell to inside, causing it to swell.
Which is NOT an effect of photo-oxidation?
a. Increase in tensile strength
b. Discoloration
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