Understanding Pathophysiology
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 58-year-old man with long-standing hypertension
develops progressive left ventricular hypertrophy.
Endomyocardial biopsy demonstrates enlarged cardiac
myocytes with increased protein synthesis but no increase in
cell number. The adaptive cellular response is most directly
driven by which intracellular process?
A. Activation of cyclin-dependent kinases promoting mitosis
B. Increased transcription of structural protein genes through
mechanosensitive signaling pathways
C. Enhanced apoptosis mediated by mitochondrial cytochrome
c release
,D. Loss of mitochondrial oxidative phosphorylation capacity
E. Telomerase-mediated extension of replicative lifespan
Correct Answer: B
Rationale:
Clinical Clue:
Cardiac myocytes enlarge rather than proliferate because they
are terminally differentiated cells with limited mitotic capacity.
Mechanism:
Mechanical stress activates intracellular signaling cascades that
alter gene transcription and increase synthesis of contractile
proteins.
Why the Correct Answer Is Right:
Hypertrophy results from increased protein production and
organelle expansion in response to workload stress, especially
in nondividing cells like cardiac muscle.
Why the Other Options Are Wrong:
A. Cardiac myocytes generally do not undergo significant
mitosis in adults.
C. Apoptosis would decrease cell mass rather than enlarge it.
D. Mitochondrial failure causes injury, not adaptive
hypertrophy.
E. Telomerase activity is associated with cellular immortality,
not physiologic hypertrophy.
Exam Trap (common misconception tested):
Confusing hypertrophy with hyperplasia.
,High-Yield Clinical Correlation:
Pressure overload from hypertension commonly produces
concentric ventricular hypertrophy through
mechanotransduction signaling.
Q2. A researcher exposes epithelial cells to a toxin that disrupts
cadherin-mediated junctions. The earliest functional
consequence is most likely impairment of:
A. Intracellular protein degradation
B. Cell-to-cell adhesion and tissue structural integrity
C. Mitochondrial ATP generation
D. DNA replication fidelity
E. Lysosomal hydrolysis of macromolecules
Correct Answer: B
Rationale:
Clinical Clue:
Cadherins are major adhesion molecules responsible for
anchoring adjacent cells.
Mechanism:
Cadherins interact with cytoskeletal proteins to maintain tissue
cohesion and structural organization.
Why the Correct Answer Is Right:
Disruption of cadherin junctions weakens intercellular
, adhesion, increasing tissue fragility and impairing coordinated
cellular behavior.
Why the Other Options Are Wrong:
A. Protein degradation is primarily proteasome-mediated.
C. ATP generation occurs in mitochondria independently of
cadherins.
D. DNA replication occurs in the nucleus.
E. Lysosomal function is unaffected directly by adhesion
molecule disruption.
Exam Trap (common misconception tested):
Assuming all membrane proteins participate primarily in
transport rather than structural communication.
High-Yield Clinical Correlation:
Loss of cadherin function contributes to tumor invasion and
metastasis.
Q3. A patient with severe malnutrition develops generalized
muscle wasting. Laboratory studies reveal reduced intracellular
ATP concentrations. Which membrane transport process is
most immediately impaired by ATP depletion?
A. Osmosis through aquaporins
B. Diffusion of oxygen across the membrane
C. Sodium-potassium pump activity
D. Facilitated diffusion of glucose
E. Movement of steroid hormones into cells
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 58-year-old man with long-standing hypertension
develops progressive left ventricular hypertrophy.
Endomyocardial biopsy demonstrates enlarged cardiac
myocytes with increased protein synthesis but no increase in
cell number. The adaptive cellular response is most directly
driven by which intracellular process?
A. Activation of cyclin-dependent kinases promoting mitosis
B. Increased transcription of structural protein genes through
mechanosensitive signaling pathways
C. Enhanced apoptosis mediated by mitochondrial cytochrome
c release
,D. Loss of mitochondrial oxidative phosphorylation capacity
E. Telomerase-mediated extension of replicative lifespan
Correct Answer: B
Rationale:
Clinical Clue:
Cardiac myocytes enlarge rather than proliferate because they
are terminally differentiated cells with limited mitotic capacity.
Mechanism:
Mechanical stress activates intracellular signaling cascades that
alter gene transcription and increase synthesis of contractile
proteins.
Why the Correct Answer Is Right:
Hypertrophy results from increased protein production and
organelle expansion in response to workload stress, especially
in nondividing cells like cardiac muscle.
Why the Other Options Are Wrong:
A. Cardiac myocytes generally do not undergo significant
mitosis in adults.
C. Apoptosis would decrease cell mass rather than enlarge it.
D. Mitochondrial failure causes injury, not adaptive
hypertrophy.
E. Telomerase activity is associated with cellular immortality,
not physiologic hypertrophy.
Exam Trap (common misconception tested):
Confusing hypertrophy with hyperplasia.
,High-Yield Clinical Correlation:
Pressure overload from hypertension commonly produces
concentric ventricular hypertrophy through
mechanotransduction signaling.
Q2. A researcher exposes epithelial cells to a toxin that disrupts
cadherin-mediated junctions. The earliest functional
consequence is most likely impairment of:
A. Intracellular protein degradation
B. Cell-to-cell adhesion and tissue structural integrity
C. Mitochondrial ATP generation
D. DNA replication fidelity
E. Lysosomal hydrolysis of macromolecules
Correct Answer: B
Rationale:
Clinical Clue:
Cadherins are major adhesion molecules responsible for
anchoring adjacent cells.
Mechanism:
Cadherins interact with cytoskeletal proteins to maintain tissue
cohesion and structural organization.
Why the Correct Answer Is Right:
Disruption of cadherin junctions weakens intercellular
, adhesion, increasing tissue fragility and impairing coordinated
cellular behavior.
Why the Other Options Are Wrong:
A. Protein degradation is primarily proteasome-mediated.
C. ATP generation occurs in mitochondria independently of
cadherins.
D. DNA replication occurs in the nucleus.
E. Lysosomal function is unaffected directly by adhesion
molecule disruption.
Exam Trap (common misconception tested):
Assuming all membrane proteins participate primarily in
transport rather than structural communication.
High-Yield Clinical Correlation:
Loss of cadherin function contributes to tumor invasion and
metastasis.
Q3. A patient with severe malnutrition develops generalized
muscle wasting. Laboratory studies reveal reduced intracellular
ATP concentrations. Which membrane transport process is
most immediately impaired by ATP depletion?
A. Osmosis through aquaporins
B. Diffusion of oxygen across the membrane
C. Sodium-potassium pump activity
D. Facilitated diffusion of glucose
E. Movement of steroid hormones into cells
