MCB 150 EXAM SCRIPT EXAMS SET
FULL SOLUTION 2026 100%
CORRECT.
⫸ What type of gene mutation is most closely associated with
DMD?
(A) missense
(B) nonsense
(C) same sense
(D) insertion
(E) deletion Answer: E
⫸ How does dystrophin stabilize the sarcolemma of muscles?
(A) It prevents the stress from sarcomere contraction from degrading
the sarcolemma.
(B) It holds multiple extracellular matrix proteins together.
(C) It coordinates muscle movement by making direct physical
contact with neighboring muscle fibers (cells).
(D) It maintains the cell in G0 so the membrane does not have to
undergo cytokinesis. Answer: A
,⫸ A human mother's genes seem to influence brain development
while a human father's genes seem to influence growth. What does
this imply?
(A) Brain development genes are on the X chromosome and growth
genes are on the Y chromosome.
(B) Mothers and fathers both imprint brain development genes.
(C) The mother imprints brain development genes and the father
imprints growth genes.
(D) The mother imprints growth genes and the father imprints brain
development genes. Answer: D
⫸ What is the probability that a mouse pup (male or female) from a
heterozygous normal-size mother (Ifg2 Igf2-) and a homozygous
dwarf father (Igf2- Igf2-) is normal-sized?
(A) 0%
(B) 25%
(C) 50%
(D) 75%
(E) 100% Answer: A
⫸ You have discovered a diploid, multicellular organism with sex
chromosome production and function resembling humans. However,
in this life form, the males have two copies of the sex chromosome M
(MM), while the females have one copy of the sex chromosome M
and one copy of the sex chromosome J (MJ). Which of the following
,statements is most likely correct about this life form? Choose all that
apply.
(A) The males of this species inactivate an M chromosome.
(B) Females of this species have structures resembling Barr bodies in
their cells.
(C) Mosaicism of M-linked traits occurs in males of the species.
(D) Males and females of this species are equally likely to practice
dosage compensation. Answer: A and C
⫸ The crossover frequency for two genes on the same chromosome
is experimentally determined to be 7 times in 1,000 offspring. This
leads to the conclusion that the genes are _______________.
(A) far from each other and 7 mu apart
(B) close to each other and 7 mu apart
(C) far from each other and 0.7 mu apart
(D) close to each other and 0.7 mu apart
(E) far from each other and 70 mu apart
(F) close to each other and 70 mu apart Answer: D
⫸ A cell has three X chromosomes, but one of those chromosomes
has a large deletion mutation in its Xic. How many Barr bodies is this
cell likely to have?
(A) 0
, (B) 1
(C) 2
(D) 3 Answer: B
⫸ Organellar genomes in higher eukarytoes are typically
_______________.
(A) derived from the nuclear genome
(B) paternally inherited
(C) maternally inherited Answer: C
⫸ Consider the following statements about mitochondria:
(1) Mitochondria have genomes which need to be replicated, but the
gene for mitochondrial DNA polymerase is not found on the
mitochondrial genome itself.
(2) Mitochondria evolved from prokaryotic ancestors with circular
genomes, but have adapted to their eukaryotic hosts by changing their
genomes to linear chromosomes for consistency.
Determine which of the options below is correct.
(A) Statements I) and II) are both true.
(B) Statements I) and II) are both false.
(C) Statement I) is true; statement II) is false.
(D) Statement I) is false; statement II) is true. Answer: C
FULL SOLUTION 2026 100%
CORRECT.
⫸ What type of gene mutation is most closely associated with
DMD?
(A) missense
(B) nonsense
(C) same sense
(D) insertion
(E) deletion Answer: E
⫸ How does dystrophin stabilize the sarcolemma of muscles?
(A) It prevents the stress from sarcomere contraction from degrading
the sarcolemma.
(B) It holds multiple extracellular matrix proteins together.
(C) It coordinates muscle movement by making direct physical
contact with neighboring muscle fibers (cells).
(D) It maintains the cell in G0 so the membrane does not have to
undergo cytokinesis. Answer: A
,⫸ A human mother's genes seem to influence brain development
while a human father's genes seem to influence growth. What does
this imply?
(A) Brain development genes are on the X chromosome and growth
genes are on the Y chromosome.
(B) Mothers and fathers both imprint brain development genes.
(C) The mother imprints brain development genes and the father
imprints growth genes.
(D) The mother imprints growth genes and the father imprints brain
development genes. Answer: D
⫸ What is the probability that a mouse pup (male or female) from a
heterozygous normal-size mother (Ifg2 Igf2-) and a homozygous
dwarf father (Igf2- Igf2-) is normal-sized?
(A) 0%
(B) 25%
(C) 50%
(D) 75%
(E) 100% Answer: A
⫸ You have discovered a diploid, multicellular organism with sex
chromosome production and function resembling humans. However,
in this life form, the males have two copies of the sex chromosome M
(MM), while the females have one copy of the sex chromosome M
and one copy of the sex chromosome J (MJ). Which of the following
,statements is most likely correct about this life form? Choose all that
apply.
(A) The males of this species inactivate an M chromosome.
(B) Females of this species have structures resembling Barr bodies in
their cells.
(C) Mosaicism of M-linked traits occurs in males of the species.
(D) Males and females of this species are equally likely to practice
dosage compensation. Answer: A and C
⫸ The crossover frequency for two genes on the same chromosome
is experimentally determined to be 7 times in 1,000 offspring. This
leads to the conclusion that the genes are _______________.
(A) far from each other and 7 mu apart
(B) close to each other and 7 mu apart
(C) far from each other and 0.7 mu apart
(D) close to each other and 0.7 mu apart
(E) far from each other and 70 mu apart
(F) close to each other and 70 mu apart Answer: D
⫸ A cell has three X chromosomes, but one of those chromosomes
has a large deletion mutation in its Xic. How many Barr bodies is this
cell likely to have?
(A) 0
, (B) 1
(C) 2
(D) 3 Answer: B
⫸ Organellar genomes in higher eukarytoes are typically
_______________.
(A) derived from the nuclear genome
(B) paternally inherited
(C) maternally inherited Answer: C
⫸ Consider the following statements about mitochondria:
(1) Mitochondria have genomes which need to be replicated, but the
gene for mitochondrial DNA polymerase is not found on the
mitochondrial genome itself.
(2) Mitochondria evolved from prokaryotic ancestors with circular
genomes, but have adapted to their eukaryotic hosts by changing their
genomes to linear chromosomes for consistency.
Determine which of the options below is correct.
(A) Statements I) and II) are both true.
(B) Statements I) and II) are both false.
(C) Statement I) is true; statement II) is false.
(D) Statement I) is false; statement II) is true. Answer: C
