Understanding Pathophysiology
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent respiratory
infections, chronic otitis media, and poor wound healing.
Genetic analysis reveals defective cadherin-mediated
intercellular attachment. The impaired function most directly
disrupts which cellular process?
A. Intracellular ATP generation through oxidative
phosphorylation
B. Stable tissue architecture and coordinated cellular signaling
C. Ribosomal assembly within the nucleolus
D. Phospholipid synthesis within the smooth endoplasmic
,reticulum
E. Lysosomal degradation of intracellular debris
Correct Answer: B
Rationale:
Clinical Clue:
Recurrent infections and impaired wound healing suggest
defective epithelial barrier integrity and tissue cohesion.
Mechanism:
Cadherins are calcium-dependent adhesion molecules that
maintain intercellular attachment and facilitate signaling
between adjacent cells.
Why the Correct Answer Is Right:
Loss of cadherin function compromises tissue organization,
epithelial stability, and coordinated cellular responses required
for repair and defense.
Why the Other Options Are Wrong:
A. Oxidative phosphorylation occurs in mitochondria and is
unrelated to cadherin defects.
C. Ribosomal assembly depends on nucleolar function.
D. Smooth ER synthesizes lipids independently of adhesion
molecules.
E. Lysosomal degradation is not mediated by cadherins.
Exam Trap (common misconception tested):
Confusing adhesion proteins with intracellular metabolic
organelles.
,High-Yield Clinical Correlation:
Defects in cell adhesion molecules contribute to metastatic
spread, epithelial fragility syndromes, and impaired immune
barrier function.
Q2. A researcher exposes hepatocytes to cyanide, resulting in
abrupt cessation of aerobic ATP production. Within minutes,
cells demonstrate swelling and membrane blebbing. The
earliest intracellular event responsible for these findings is
failure of:
A. DNA transcription
B. Lysosomal enzyme synthesis
C. Sodium-potassium ATPase activity
D. Microtubule polymerization
E. Golgi-mediated protein packaging
Correct Answer: C
Rationale:
Clinical Clue:
Rapid cellular swelling after ATP depletion indicates osmotic
dysregulation.
Mechanism:
ATP depletion disables membrane ion pumps, especially the
Na+/K+ ATPase, causing sodium and water influx.
, Why the Correct Answer Is Right:
Loss of sodium-potassium pump function is the earliest major
consequence of severe ATP depletion and produces acute
cellular swelling.
Why the Other Options Are Wrong:
A. Transcription decreases later and does not directly cause
acute swelling.
B. Lysosomal enzyme synthesis is not the earliest ATP-
dependent failure.
D. Cytoskeletal changes occur secondarily.
E. Protein packaging defects develop later in injury progression.
Exam Trap (common misconception tested):
Assuming mitochondrial injury causes immediate membrane
rupture rather than ion transport failure first.
High-Yield Clinical Correlation:
Reversible cellular injury commonly begins with ATP depletion
and membrane pump dysfunction.
Q3. A patient with severe vitamin B12 deficiency develops
megaloblastic changes in rapidly dividing tissues. The abnormal
cellular morphology most directly reflects impaired:
A. Cytoplasmic protein translation
B. Mitotic spindle anchoring
C. DNA synthesis during the S phase
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent respiratory
infections, chronic otitis media, and poor wound healing.
Genetic analysis reveals defective cadherin-mediated
intercellular attachment. The impaired function most directly
disrupts which cellular process?
A. Intracellular ATP generation through oxidative
phosphorylation
B. Stable tissue architecture and coordinated cellular signaling
C. Ribosomal assembly within the nucleolus
D. Phospholipid synthesis within the smooth endoplasmic
,reticulum
E. Lysosomal degradation of intracellular debris
Correct Answer: B
Rationale:
Clinical Clue:
Recurrent infections and impaired wound healing suggest
defective epithelial barrier integrity and tissue cohesion.
Mechanism:
Cadherins are calcium-dependent adhesion molecules that
maintain intercellular attachment and facilitate signaling
between adjacent cells.
Why the Correct Answer Is Right:
Loss of cadherin function compromises tissue organization,
epithelial stability, and coordinated cellular responses required
for repair and defense.
Why the Other Options Are Wrong:
A. Oxidative phosphorylation occurs in mitochondria and is
unrelated to cadherin defects.
C. Ribosomal assembly depends on nucleolar function.
D. Smooth ER synthesizes lipids independently of adhesion
molecules.
E. Lysosomal degradation is not mediated by cadherins.
Exam Trap (common misconception tested):
Confusing adhesion proteins with intracellular metabolic
organelles.
,High-Yield Clinical Correlation:
Defects in cell adhesion molecules contribute to metastatic
spread, epithelial fragility syndromes, and impaired immune
barrier function.
Q2. A researcher exposes hepatocytes to cyanide, resulting in
abrupt cessation of aerobic ATP production. Within minutes,
cells demonstrate swelling and membrane blebbing. The
earliest intracellular event responsible for these findings is
failure of:
A. DNA transcription
B. Lysosomal enzyme synthesis
C. Sodium-potassium ATPase activity
D. Microtubule polymerization
E. Golgi-mediated protein packaging
Correct Answer: C
Rationale:
Clinical Clue:
Rapid cellular swelling after ATP depletion indicates osmotic
dysregulation.
Mechanism:
ATP depletion disables membrane ion pumps, especially the
Na+/K+ ATPase, causing sodium and water influx.
, Why the Correct Answer Is Right:
Loss of sodium-potassium pump function is the earliest major
consequence of severe ATP depletion and produces acute
cellular swelling.
Why the Other Options Are Wrong:
A. Transcription decreases later and does not directly cause
acute swelling.
B. Lysosomal enzyme synthesis is not the earliest ATP-
dependent failure.
D. Cytoskeletal changes occur secondarily.
E. Protein packaging defects develop later in injury progression.
Exam Trap (common misconception tested):
Assuming mitochondrial injury causes immediate membrane
rupture rather than ion transport failure first.
High-Yield Clinical Correlation:
Reversible cellular injury commonly begins with ATP depletion
and membrane pump dysfunction.
Q3. A patient with severe vitamin B12 deficiency develops
megaloblastic changes in rapidly dividing tissues. The abnormal
cellular morphology most directly reflects impaired:
A. Cytoplasmic protein translation
B. Mitotic spindle anchoring
C. DNA synthesis during the S phase
