HESI A2 Biology Multiple Choice Questions With Complete
Solutions
a distinct difference between a plant cell and an animal cell is
the presence of
a) ribosomes
b) mitochondria
c) a cell wall
d) a nucleus Correct Answer c) a cell wall: a plant cell is
enveloped by a cell wall, but animal cells do not possess a cell
wall
a scientist takes DNA samples from a cell culture at two
different times, each same having the same cell count. in the
first sample, he finds that there is a 6.5 pg of DNA whereas in
the second sample, he finds that there is a 13 pg of DNA. which
state of the cell cycle is the first sample in?
a) interphase G1
b) interphase S
c) interphase G2
d) mitotic phase Correct Answer a) interphase G1: during the
G1 phase of interphase, the cell has not replicated its DNA,
doubling the amount of DNA in the cell
a student places a cell with 50 mM intracellular ion content into
a solution containing a 20 mM ion content. which of the
following will happen in this system?
a) water will move out of the cell, decreasing the size of the cell
,b) water will move into the cell, increasing the size of the cell
c) ions will move into the cell
d) there will be no movement of water or ions across the cell
membrane Correct Answer b) water will move into the cell,
increasing the size of the cell: the concentration of ions is higher
inside the cell than outside, so water will move into the cell from
the environment, increasing the size of the cell
all living organisms on earth utilize?
a) oxygen
b) light
c) sexual reproduction
d) a triplet genetic code Correct Answer d) a triplet codon
all of the following molecules are used in the Calvin Cycle
EXCEPT
a) O2
b) CO2
c) ATP
d) NADPH Correct Answer a) O2: is released during the light-
dependent stage of photosynthesis and is not used during the
Calvin Cycle. the other choices are used during the Calvin Cycle
to produce glucose
alleles for brown eyes (B) are dominant over alleles for blue
eyes (b). if two parents are both heterozygous for this gene, what
is the percent chance that their offspring will have brown eyes?
a) 25
, b) 50
c) 75
d) 100 Correct Answer c) 75: the punnet square shows that
there is a 75 percent chance the child will have the dominant B
gene, and thus have brown eyes
at the ACU codon, the amino acid threonine will be inserted in
the polypeptide. which of the following anticodons would be
found on the tRNA molecule that carries threonine?
a) ACU
b) UCA
c) TGA
d) UGA Correct Answer d) UGA: anticodons and codons are
complementary - the complement of the codon ACU is the
anticodon UGA
at the end of which phase of mitosis are chromosomes first
clearly visible under the light microscope?
a) interphase
b) prophase
c) metaphase
d) anaphase Correct Answer b) prophase: during prophase, the
DNA replicated during interphase condenses into chromosomes,
which are clearly visible under a light microscope
carbohydrates are converted into _____ in order to provide
energy. Correct Answer glucose
Solutions
a distinct difference between a plant cell and an animal cell is
the presence of
a) ribosomes
b) mitochondria
c) a cell wall
d) a nucleus Correct Answer c) a cell wall: a plant cell is
enveloped by a cell wall, but animal cells do not possess a cell
wall
a scientist takes DNA samples from a cell culture at two
different times, each same having the same cell count. in the
first sample, he finds that there is a 6.5 pg of DNA whereas in
the second sample, he finds that there is a 13 pg of DNA. which
state of the cell cycle is the first sample in?
a) interphase G1
b) interphase S
c) interphase G2
d) mitotic phase Correct Answer a) interphase G1: during the
G1 phase of interphase, the cell has not replicated its DNA,
doubling the amount of DNA in the cell
a student places a cell with 50 mM intracellular ion content into
a solution containing a 20 mM ion content. which of the
following will happen in this system?
a) water will move out of the cell, decreasing the size of the cell
,b) water will move into the cell, increasing the size of the cell
c) ions will move into the cell
d) there will be no movement of water or ions across the cell
membrane Correct Answer b) water will move into the cell,
increasing the size of the cell: the concentration of ions is higher
inside the cell than outside, so water will move into the cell from
the environment, increasing the size of the cell
all living organisms on earth utilize?
a) oxygen
b) light
c) sexual reproduction
d) a triplet genetic code Correct Answer d) a triplet codon
all of the following molecules are used in the Calvin Cycle
EXCEPT
a) O2
b) CO2
c) ATP
d) NADPH Correct Answer a) O2: is released during the light-
dependent stage of photosynthesis and is not used during the
Calvin Cycle. the other choices are used during the Calvin Cycle
to produce glucose
alleles for brown eyes (B) are dominant over alleles for blue
eyes (b). if two parents are both heterozygous for this gene, what
is the percent chance that their offspring will have brown eyes?
a) 25
, b) 50
c) 75
d) 100 Correct Answer c) 75: the punnet square shows that
there is a 75 percent chance the child will have the dominant B
gene, and thus have brown eyes
at the ACU codon, the amino acid threonine will be inserted in
the polypeptide. which of the following anticodons would be
found on the tRNA molecule that carries threonine?
a) ACU
b) UCA
c) TGA
d) UGA Correct Answer d) UGA: anticodons and codons are
complementary - the complement of the codon ACU is the
anticodon UGA
at the end of which phase of mitosis are chromosomes first
clearly visible under the light microscope?
a) interphase
b) prophase
c) metaphase
d) anaphase Correct Answer b) prophase: during prophase, the
DNA replicated during interphase condenses into chromosomes,
which are clearly visible under a light microscope
carbohydrates are converted into _____ in order to provide
energy. Correct Answer glucose
