McCance & Huether’s Pathophysiology
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
Chapter 1: Cellular Biology
Q1. A research participant is found to carry a mutation
that selectively disrupts mitochondrial inner membrane
integrity while preserving the outer membrane. The
patient reports profound exercise intolerance despite
, normal oxygen delivery. Which cellular consequence most
directly explains the symptoms?
A. Failure of glycolytic ATP production
B. Impaired oxidative phosphorylation and ATP generation
C. Excess lysosomal protein degradation
D. Reduced DNA transcription within the nucleus
Correct Answer: B
Rationale:
• Clinical Clue: Exercise intolerance with adequate oxygen
supply suggests impaired energy extraction rather than
oxygen delivery.
• Mechanism: The inner mitochondrial membrane houses
the electron transport chain and ATP synthase.
• Why the Correct Answer Is Right: Loss of membrane
integrity collapses proton gradients, preventing ATP
production through oxidative phosphorylation.
• Why the Other Options Are Wrong: Glycolysis occurs in
cytoplasm; lysosomes degrade cellular material; nuclear
transcription remains independent.
• Exam Trap: Associating all ATP production with glycolysis.
• High-Yield Clinical Correlation: Mitochondrial dysfunction
disproportionately affects skeletal muscle, myocardium,
and neurons.
,• Memory Anchor: Inner mitochondrial membrane =
cellular power converter.
Q2. An epithelial biopsy demonstrates intact cells but
marked loss of organized tissue architecture due to
defective proteins connecting adjacent cells. Which
pathophysiologic change best accounts for this finding?
A. Impaired cell-to-cell adhesion
B. Accelerated apoptosis
C. Increased intracellular calcium storage
D. Enhanced membrane transport
Correct Answer: A
Rationale:
• Clinical Clue: Preserved individual cells with disorganized
tissue points to adhesion failure.
• Mechanism: Adhesion molecules maintain structural
integrity and coordinate tissue function.
• Why the Correct Answer Is Right: Disruption of cellular
junctions weakens cohesion and tissue organization.
• Why the Other Options Are Wrong: Apoptosis decreases
cell number; calcium storage and transport do not explain
architectural collapse.
• Exam Trap: Assuming tissue dysfunction always reflects
cell death.
, • High-Yield Clinical Correlation: Adhesion defects
contribute to blistering disorders and metastatic spread.
• Memory Anchor: Cells survive; tissues fail when adhesion
disappears.
Q3. A patient develops severe diarrhea caused by
excessive activation of intestinal chloride channels through
persistent intracellular second messenger signaling. Which
cellular process is most directly altered?
A. Signal transduction
B. DNA replication
C. Protein folding
D. Nuclear transport
Correct Answer: A
Rationale:
• Clinical Clue: Persistent receptor-mediated ion secretion
suggests altered intracellular signaling.
• Mechanism: Signal transduction converts extracellular
signals into intracellular responses.
• Why the Correct Answer Is Right: Second messengers
amplify receptor activity and alter membrane transport.
• Why the Other Options Are Wrong: Replication, folding,
and nuclear transport are unrelated to acute secretion
changes.
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
Chapter 1: Cellular Biology
Q1. A research participant is found to carry a mutation
that selectively disrupts mitochondrial inner membrane
integrity while preserving the outer membrane. The
patient reports profound exercise intolerance despite
, normal oxygen delivery. Which cellular consequence most
directly explains the symptoms?
A. Failure of glycolytic ATP production
B. Impaired oxidative phosphorylation and ATP generation
C. Excess lysosomal protein degradation
D. Reduced DNA transcription within the nucleus
Correct Answer: B
Rationale:
• Clinical Clue: Exercise intolerance with adequate oxygen
supply suggests impaired energy extraction rather than
oxygen delivery.
• Mechanism: The inner mitochondrial membrane houses
the electron transport chain and ATP synthase.
• Why the Correct Answer Is Right: Loss of membrane
integrity collapses proton gradients, preventing ATP
production through oxidative phosphorylation.
• Why the Other Options Are Wrong: Glycolysis occurs in
cytoplasm; lysosomes degrade cellular material; nuclear
transcription remains independent.
• Exam Trap: Associating all ATP production with glycolysis.
• High-Yield Clinical Correlation: Mitochondrial dysfunction
disproportionately affects skeletal muscle, myocardium,
and neurons.
,• Memory Anchor: Inner mitochondrial membrane =
cellular power converter.
Q2. An epithelial biopsy demonstrates intact cells but
marked loss of organized tissue architecture due to
defective proteins connecting adjacent cells. Which
pathophysiologic change best accounts for this finding?
A. Impaired cell-to-cell adhesion
B. Accelerated apoptosis
C. Increased intracellular calcium storage
D. Enhanced membrane transport
Correct Answer: A
Rationale:
• Clinical Clue: Preserved individual cells with disorganized
tissue points to adhesion failure.
• Mechanism: Adhesion molecules maintain structural
integrity and coordinate tissue function.
• Why the Correct Answer Is Right: Disruption of cellular
junctions weakens cohesion and tissue organization.
• Why the Other Options Are Wrong: Apoptosis decreases
cell number; calcium storage and transport do not explain
architectural collapse.
• Exam Trap: Assuming tissue dysfunction always reflects
cell death.
, • High-Yield Clinical Correlation: Adhesion defects
contribute to blistering disorders and metastatic spread.
• Memory Anchor: Cells survive; tissues fail when adhesion
disappears.
Q3. A patient develops severe diarrhea caused by
excessive activation of intestinal chloride channels through
persistent intracellular second messenger signaling. Which
cellular process is most directly altered?
A. Signal transduction
B. DNA replication
C. Protein folding
D. Nuclear transport
Correct Answer: A
Rationale:
• Clinical Clue: Persistent receptor-mediated ion secretion
suggests altered intracellular signaling.
• Mechanism: Signal transduction converts extracellular
signals into intracellular responses.
• Why the Correct Answer Is Right: Second messengers
amplify receptor activity and alter membrane transport.
• Why the Other Options Are Wrong: Replication, folding,
and nuclear transport are unrelated to acute secretion
changes.
