MCAT Biology Practice Exam
Questions and Answers
Hyperbaric oxygen may be used as a treatment for certain types of bacterial infections.
In this therapy, the patient is placed in a which the partial pressure of oxygen is
significantly increased, increasing the partial pressure of oxygen in the patient's tissues.
This treatment is most likely used for infections with:
A. obligate aerobic bacteria
B. facultative anaerobix bacteria
C. aerotolerant anarobic bacteria
D. obligate anaerobic bacteria - ANS-D
Which of the following does NOT describe connective tissue cells?
A. They account for most cells in muscles, bones, and tendons
B. They secrete substances to form the extracellular matrix
C. in organs, they tend to form the stroma
D. In organs, they provide support for epithelial cells - ANS-A
Which of the following types of nucleic acid could form the genome of a virus?
I. Single-stranded RNA
II. Double-stranded RNA
III. Single-stranded DNA
A. I only
B. II only
C. I and II only
D I, II and III - ANS-D
Which of the following activities occurs in the Golgi apparatus?
A. Synthesis of proteins
B. Modification and distribution of proteins
C. Breakdown of lipids and carbohydrates
D. Production of ATP - ANS-B
Mitochondrial DNA is:
I. circular
II. self-replicating
III. single-stranded
,A. I only
B. II only
C. I and II only
D. I, II and III - ANS-C
Which of the following is NOT a function of the smooth endoplasmic reticulum?
A. Lipid synthesis
B. Poison detoxification
C. Protein synthesis
D. Transport of proteins - ANS-C
What is the main function of the nucleolus?
A. Ribosomal RNA synthesis
B. DNA replication
C. Cell division
D. Chromosome assembly - ANS-A
Which of the following organelles is surrounded by a single membrane?
A. Lysosomes
B. Mitochondria
C. Nuclei
D. Ribosomes - ANS-A
Which of the following is NOT a difference that would allow one to distinguish a
prokaryotic and a eukaryotic cell?
A. Ribosomal subunit weight
B. Presence of a nucleus
C. Presence of a membrane on the outside surface of the cell
D. Presence of membrane-bound organelles - ANS-C
Which of the following does NOT contain tubulin?
A. Cilia
B. Flagella
C. Microfilaments
D. Centrioles - ANS-C
Herpes simplex virus (HSV) enters the human body and remains dormant in the
nervous system until is produces an outbreak after exposure to heat, radiation, or other
stimuli. Which of the following statements correctly describes HSV?
,A. While it remains dormant in the nervous system, the virus is in its lytic cycle
B. During an outbreak the virus is in the lysogenic cycle
C. Herpes simplex virus adds it genetic information to the genetic information of the cell
D. The herpes simplex virus contains a tail sheath and tail fibers - ANS-C
Resistance to antibiotics is a well-recognized medical problem. Which mechanism(s)
can account for a bacterium's ability to increase its genetic variability and thus adapt
itself to resist different antibiotics?
I. Binary Fission
II. Conjugation
III. Transduction
A. I and II only
B. I and III only
C. II and III only
D. I, II and III - ANS-C
A bacterial cell is noted to be resistant to penicillin. The bacterium is transferred to a
colony that lacks the fertility factor, and the rest of the colony does not become resistant
to penicillin. However, the penicillin-resistant cell has started to exhibit other phenotypic
characteristics, including secretion of a novel protein. Which of the following methods of
bacterial recombination is NOT likely to account for this change?
A. Conjugation
B. Transformation
C. Transduction
D. Infection with a bacteriophage - ANS-A
In Alzheimers disease, a protein called the amyloid precursor protein (APP) is cleaved
to form a protein called B-amyloid. This protein has a B-pleated sheet structure and
precipitates to form plaques in the brain. This mechanism of disease is most similar to
which of the following pathogens?
A. Bacteria
B. Viruses
C. Prions
D. Viroids - ANS-C
Which of the following is the correct sequence of the development of a mature sperm
cell?
A. Spermatid -> spermatocyte -> spermatogonium -> 2 degree spermatocyte ->
spermatozoan
B. Spermatogonium -> 1 degree spermatocyte -> 2 degree spermatocyte -> spermatid -
> spermatozoan
, C. Spermatozoan -> 1 degree spermatocyte -> 2 degree spermatocyte ->
spermatogonium -> spermatid
D. Spermatogonium -> 1 degree spermatocyte -> 2 degree spermatocyte ->
spermatozoan -> spermatid - ANS-B
Which of the following correctly pairs the stage of development of an egg cell with the
relevant point in a woman's life cycle?
A. From birth to menarche - prophase II
B. At ovulation - metaphase I
C. At ovulation - metaphase II
D. At fertilization - prophase II - ANS-C
Some studies suggest that in patients with Alzheimer's disease, there is a defect in the
way the spindle apparatus attaches to the kinetochore fibers. At which stage of mitotic
division would one first expect to be able to visualize this problem?
A. Prophase
B. Metaphase
C. Anaphase
D. Telophase - ANS-A
A researcher wishes to incorporate a radiolabeled deoxyadenine into the genome of
one of the two daughter cells that would arise as a result of mitosis. What is the latest
stage of cellular development during which the radiolabeled deoxyadenine could be
added to achieve this result?
A. G1
B. G2
C. M
D. S - ANS-D
Certain ovarian tumors called granulosa cell tumors are known to produce excessive
levels of estrogen. A physician who diagnoses a granulosa cell tumor should look for a
secondary cancer in which of the following parts of the reproductive tract?
A. Fallopian tube
B. Cervix
C. Endometrium
D. Vagina - ANS-C
Upon ovulation, the oocyte is released into the:
A. fallopian tube
B. follicle
C. abdominal cavity
Questions and Answers
Hyperbaric oxygen may be used as a treatment for certain types of bacterial infections.
In this therapy, the patient is placed in a which the partial pressure of oxygen is
significantly increased, increasing the partial pressure of oxygen in the patient's tissues.
This treatment is most likely used for infections with:
A. obligate aerobic bacteria
B. facultative anaerobix bacteria
C. aerotolerant anarobic bacteria
D. obligate anaerobic bacteria - ANS-D
Which of the following does NOT describe connective tissue cells?
A. They account for most cells in muscles, bones, and tendons
B. They secrete substances to form the extracellular matrix
C. in organs, they tend to form the stroma
D. In organs, they provide support for epithelial cells - ANS-A
Which of the following types of nucleic acid could form the genome of a virus?
I. Single-stranded RNA
II. Double-stranded RNA
III. Single-stranded DNA
A. I only
B. II only
C. I and II only
D I, II and III - ANS-D
Which of the following activities occurs in the Golgi apparatus?
A. Synthesis of proteins
B. Modification and distribution of proteins
C. Breakdown of lipids and carbohydrates
D. Production of ATP - ANS-B
Mitochondrial DNA is:
I. circular
II. self-replicating
III. single-stranded
,A. I only
B. II only
C. I and II only
D. I, II and III - ANS-C
Which of the following is NOT a function of the smooth endoplasmic reticulum?
A. Lipid synthesis
B. Poison detoxification
C. Protein synthesis
D. Transport of proteins - ANS-C
What is the main function of the nucleolus?
A. Ribosomal RNA synthesis
B. DNA replication
C. Cell division
D. Chromosome assembly - ANS-A
Which of the following organelles is surrounded by a single membrane?
A. Lysosomes
B. Mitochondria
C. Nuclei
D. Ribosomes - ANS-A
Which of the following is NOT a difference that would allow one to distinguish a
prokaryotic and a eukaryotic cell?
A. Ribosomal subunit weight
B. Presence of a nucleus
C. Presence of a membrane on the outside surface of the cell
D. Presence of membrane-bound organelles - ANS-C
Which of the following does NOT contain tubulin?
A. Cilia
B. Flagella
C. Microfilaments
D. Centrioles - ANS-C
Herpes simplex virus (HSV) enters the human body and remains dormant in the
nervous system until is produces an outbreak after exposure to heat, radiation, or other
stimuli. Which of the following statements correctly describes HSV?
,A. While it remains dormant in the nervous system, the virus is in its lytic cycle
B. During an outbreak the virus is in the lysogenic cycle
C. Herpes simplex virus adds it genetic information to the genetic information of the cell
D. The herpes simplex virus contains a tail sheath and tail fibers - ANS-C
Resistance to antibiotics is a well-recognized medical problem. Which mechanism(s)
can account for a bacterium's ability to increase its genetic variability and thus adapt
itself to resist different antibiotics?
I. Binary Fission
II. Conjugation
III. Transduction
A. I and II only
B. I and III only
C. II and III only
D. I, II and III - ANS-C
A bacterial cell is noted to be resistant to penicillin. The bacterium is transferred to a
colony that lacks the fertility factor, and the rest of the colony does not become resistant
to penicillin. However, the penicillin-resistant cell has started to exhibit other phenotypic
characteristics, including secretion of a novel protein. Which of the following methods of
bacterial recombination is NOT likely to account for this change?
A. Conjugation
B. Transformation
C. Transduction
D. Infection with a bacteriophage - ANS-A
In Alzheimers disease, a protein called the amyloid precursor protein (APP) is cleaved
to form a protein called B-amyloid. This protein has a B-pleated sheet structure and
precipitates to form plaques in the brain. This mechanism of disease is most similar to
which of the following pathogens?
A. Bacteria
B. Viruses
C. Prions
D. Viroids - ANS-C
Which of the following is the correct sequence of the development of a mature sperm
cell?
A. Spermatid -> spermatocyte -> spermatogonium -> 2 degree spermatocyte ->
spermatozoan
B. Spermatogonium -> 1 degree spermatocyte -> 2 degree spermatocyte -> spermatid -
> spermatozoan
, C. Spermatozoan -> 1 degree spermatocyte -> 2 degree spermatocyte ->
spermatogonium -> spermatid
D. Spermatogonium -> 1 degree spermatocyte -> 2 degree spermatocyte ->
spermatozoan -> spermatid - ANS-B
Which of the following correctly pairs the stage of development of an egg cell with the
relevant point in a woman's life cycle?
A. From birth to menarche - prophase II
B. At ovulation - metaphase I
C. At ovulation - metaphase II
D. At fertilization - prophase II - ANS-C
Some studies suggest that in patients with Alzheimer's disease, there is a defect in the
way the spindle apparatus attaches to the kinetochore fibers. At which stage of mitotic
division would one first expect to be able to visualize this problem?
A. Prophase
B. Metaphase
C. Anaphase
D. Telophase - ANS-A
A researcher wishes to incorporate a radiolabeled deoxyadenine into the genome of
one of the two daughter cells that would arise as a result of mitosis. What is the latest
stage of cellular development during which the radiolabeled deoxyadenine could be
added to achieve this result?
A. G1
B. G2
C. M
D. S - ANS-D
Certain ovarian tumors called granulosa cell tumors are known to produce excessive
levels of estrogen. A physician who diagnoses a granulosa cell tumor should look for a
secondary cancer in which of the following parts of the reproductive tract?
A. Fallopian tube
B. Cervix
C. Endometrium
D. Vagina - ANS-C
Upon ovulation, the oocyte is released into the:
A. fallopian tube
B. follicle
C. abdominal cavity
