McCance & Huether’s Pathophysiology
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
,Q1. A 5-year-old boy presents with recurrent pyogenic
infections and delayed wound healing. Neutrophil studies
reveal impaired migration into infected tissues despite normal
neutrophil counts. Defective expression of integrins on
leukocyte surfaces is identified. The clinical manifestations are
most directly explained by disruption of which cellular process?
A. ATP-dependent lysosomal degradation
B. Cell-to-cell adhesion and transmigration
C. Oxidative phosphorylation within mitochondria
D. DNA repair during mitosis
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent bacterial infections with impaired
neutrophil migration suggests defective leukocyte
adhesion.
• Mechanism: Integrins mediate adhesion between
leukocytes and endothelial cells, enabling diapedesis into
tissues.
• Why the Correct Answer Is Right: Loss of integrin-
mediated adhesion prevents immune cells from exiting
circulation and reaching sites of infection.
• Why the Other Options Are Wrong:
o A: Lysosomal degradation affects intracellular killing,
not migration.
, o C: Oxidative phosphorylation defects cause energy
failure syndromes.
o D: DNA repair abnormalities predispose to
malignancy rather than impaired chemotaxis.
• Exam Trap: Normal leukocyte counts do not exclude
defective immune function.
• High-Yield Clinical Correlation: Leukocyte adhesion
deficiency classically presents with delayed umbilical cord
separation and absent pus formation.
• Memory Anchor: “Integrins let immune cells grip and
migrate.”
Q2. A researcher exposes cultured hepatocytes to a toxin that
selectively disrupts rough endoplasmic reticulum function.
Which cellular abnormality would most likely develop first?
A. Impaired phospholipid synthesis
B. Reduced intracellular calcium storage
C. Decreased synthesis of secretory proteins
D. Failure of oxidative ATP generation
Correct Answer: C
Rationale:
• Clinical Clue: Rough endoplasmic reticulum (RER) is
studded with ribosomes involved in protein synthesis.
, • Mechanism: The RER synthesizes membrane-bound and
secreted proteins.
• Why the Correct Answer Is Right: Hepatocytes depend
heavily on RER activity to produce plasma proteins and
enzymes.
• Why the Other Options Are Wrong:
o A: Smooth ER primarily handles lipid synthesis.
o B: Sarcoplasmic reticulum is specialized for calcium
storage.
o D: ATP generation occurs in mitochondria.
• Exam Trap: Students often confuse rough and smooth ER
functions.
• High-Yield Clinical Correlation: Plasma cells have abundant
RER because of intense immunoglobulin production.
• Memory Anchor: “Rough ER = ribosomes = proteins.”
Q3. A patient with chronic alcoholism develops hepatocellular
injury characterized by swollen mitochondria and decreased
ATP production. Which membrane transport process is most
directly impaired as ATP levels decline?
A. Osmosis
B. Facilitated diffusion
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
,Q1. A 5-year-old boy presents with recurrent pyogenic
infections and delayed wound healing. Neutrophil studies
reveal impaired migration into infected tissues despite normal
neutrophil counts. Defective expression of integrins on
leukocyte surfaces is identified. The clinical manifestations are
most directly explained by disruption of which cellular process?
A. ATP-dependent lysosomal degradation
B. Cell-to-cell adhesion and transmigration
C. Oxidative phosphorylation within mitochondria
D. DNA repair during mitosis
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent bacterial infections with impaired
neutrophil migration suggests defective leukocyte
adhesion.
• Mechanism: Integrins mediate adhesion between
leukocytes and endothelial cells, enabling diapedesis into
tissues.
• Why the Correct Answer Is Right: Loss of integrin-
mediated adhesion prevents immune cells from exiting
circulation and reaching sites of infection.
• Why the Other Options Are Wrong:
o A: Lysosomal degradation affects intracellular killing,
not migration.
, o C: Oxidative phosphorylation defects cause energy
failure syndromes.
o D: DNA repair abnormalities predispose to
malignancy rather than impaired chemotaxis.
• Exam Trap: Normal leukocyte counts do not exclude
defective immune function.
• High-Yield Clinical Correlation: Leukocyte adhesion
deficiency classically presents with delayed umbilical cord
separation and absent pus formation.
• Memory Anchor: “Integrins let immune cells grip and
migrate.”
Q2. A researcher exposes cultured hepatocytes to a toxin that
selectively disrupts rough endoplasmic reticulum function.
Which cellular abnormality would most likely develop first?
A. Impaired phospholipid synthesis
B. Reduced intracellular calcium storage
C. Decreased synthesis of secretory proteins
D. Failure of oxidative ATP generation
Correct Answer: C
Rationale:
• Clinical Clue: Rough endoplasmic reticulum (RER) is
studded with ribosomes involved in protein synthesis.
, • Mechanism: The RER synthesizes membrane-bound and
secreted proteins.
• Why the Correct Answer Is Right: Hepatocytes depend
heavily on RER activity to produce plasma proteins and
enzymes.
• Why the Other Options Are Wrong:
o A: Smooth ER primarily handles lipid synthesis.
o B: Sarcoplasmic reticulum is specialized for calcium
storage.
o D: ATP generation occurs in mitochondria.
• Exam Trap: Students often confuse rough and smooth ER
functions.
• High-Yield Clinical Correlation: Plasma cells have abundant
RER because of intense immunoglobulin production.
• Memory Anchor: “Rough ER = ribosomes = proteins.”
Q3. A patient with chronic alcoholism develops hepatocellular
injury characterized by swollen mitochondria and decreased
ATP production. Which membrane transport process is most
directly impaired as ATP levels decline?
A. Osmosis
B. Facilitated diffusion
