McCance & Huether’s Pathophysiology
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
Q1. A 6-year-old child is diagnosed with recurrent
pyogenic infections caused by impaired neutrophil
migration into tissues. Genetic analysis reveals defective
leukocyte integrin activation despite normal neutrophil
counts. The inability of neutrophils to firmly adhere to
vascular endothelium most directly reflects dysfunction of
which cellular process?
, A. Microtubule polymerization during mitosis
B. Cell-to-cell adhesion mediated by surface adhesion
molecules
C. Oxidative phosphorylation within mitochondria
D. DNA transcription within the nucleus
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent bacterial infections with defective
neutrophil adhesion suggests impaired leukocyte-
endothelial interaction.
• Mechanism: Integrins are adhesion molecules essential for
firm leukocyte attachment to endothelial ICAMs before
diapedesis.
• Why the Correct Answer Is Right: Cell adhesion molecules
coordinate tissue integrity and immune cell trafficking.
Defective integrin activation disrupts neutrophil
extravasation.
• Why the Other Options Are Wrong:
o A: Microtubules affect intracellular transport and
mitosis, not endothelial adhesion.
o C: Oxidative phosphorylation defects produce energy
failure syndromes, not isolated adhesion defects.
o D: Transcription abnormalities would cause broader
cellular dysfunction.
,• Exam Trap: Confusing leukocyte movement with
cytoskeletal disorders rather than adhesion receptor
failure.
• High-Yield Clinical Correlation: Leukocyte adhesion
deficiency presents with delayed cord separation and
recurrent infections without pus formation.
• Memory Anchor: “Integrins anchor immune cells before
they enter tissue.”
Q2. A researcher exposes cultured hepatocytes to a toxin
that selectively disrupts rough endoplasmic reticulum
function. Which cellular abnormality would most likely
result?
A. Impaired ATP generation
B. Defective lipid degradation
C. Reduced synthesis of secretory proteins
D. Failure of lysosomal acidification
Correct Answer: C
Rationale:
• Clinical Clue: Rough endoplasmic reticulum (RER) is
studded with ribosomes.
• Mechanism: The RER synthesizes proteins destined for
secretion, membranes, or lysosomes.
, • Why the Correct Answer Is Right: Hepatocytes rely heavily
on RER for plasma protein synthesis including albumin and
clotting factors.
• Why the Other Options Are Wrong:
o A: ATP generation occurs primarily in mitochondria.
o B: Lipid degradation mainly involves peroxisomes and
lysosomes.
o D: Lysosomal acidification depends on proton pumps
within lysosomal membranes.
• Exam Trap: Confusing smooth ER with rough ER functions.
• High-Yield Clinical Correlation: Cells specialized for
secretion contain abundant RER.
• Memory Anchor: “Rough ER = ribosomes = exported
proteins.”
Q3. A patient develops severe muscle fatigue after
exposure to cyanide, which inhibits cytochrome oxidase in
mitochondria. Which pathophysiologic consequence best
accounts for the rapid cellular dysfunction?
A. Accumulation of intracellular calcium due to ATP
depletion
B. Increased DNA replication within the nucleus
C. Enhanced lysosomal protein synthesis
D. Excessive sodium extrusion from the cell
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
Q1. A 6-year-old child is diagnosed with recurrent
pyogenic infections caused by impaired neutrophil
migration into tissues. Genetic analysis reveals defective
leukocyte integrin activation despite normal neutrophil
counts. The inability of neutrophils to firmly adhere to
vascular endothelium most directly reflects dysfunction of
which cellular process?
, A. Microtubule polymerization during mitosis
B. Cell-to-cell adhesion mediated by surface adhesion
molecules
C. Oxidative phosphorylation within mitochondria
D. DNA transcription within the nucleus
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent bacterial infections with defective
neutrophil adhesion suggests impaired leukocyte-
endothelial interaction.
• Mechanism: Integrins are adhesion molecules essential for
firm leukocyte attachment to endothelial ICAMs before
diapedesis.
• Why the Correct Answer Is Right: Cell adhesion molecules
coordinate tissue integrity and immune cell trafficking.
Defective integrin activation disrupts neutrophil
extravasation.
• Why the Other Options Are Wrong:
o A: Microtubules affect intracellular transport and
mitosis, not endothelial adhesion.
o C: Oxidative phosphorylation defects produce energy
failure syndromes, not isolated adhesion defects.
o D: Transcription abnormalities would cause broader
cellular dysfunction.
,• Exam Trap: Confusing leukocyte movement with
cytoskeletal disorders rather than adhesion receptor
failure.
• High-Yield Clinical Correlation: Leukocyte adhesion
deficiency presents with delayed cord separation and
recurrent infections without pus formation.
• Memory Anchor: “Integrins anchor immune cells before
they enter tissue.”
Q2. A researcher exposes cultured hepatocytes to a toxin
that selectively disrupts rough endoplasmic reticulum
function. Which cellular abnormality would most likely
result?
A. Impaired ATP generation
B. Defective lipid degradation
C. Reduced synthesis of secretory proteins
D. Failure of lysosomal acidification
Correct Answer: C
Rationale:
• Clinical Clue: Rough endoplasmic reticulum (RER) is
studded with ribosomes.
• Mechanism: The RER synthesizes proteins destined for
secretion, membranes, or lysosomes.
, • Why the Correct Answer Is Right: Hepatocytes rely heavily
on RER for plasma protein synthesis including albumin and
clotting factors.
• Why the Other Options Are Wrong:
o A: ATP generation occurs primarily in mitochondria.
o B: Lipid degradation mainly involves peroxisomes and
lysosomes.
o D: Lysosomal acidification depends on proton pumps
within lysosomal membranes.
• Exam Trap: Confusing smooth ER with rough ER functions.
• High-Yield Clinical Correlation: Cells specialized for
secretion contain abundant RER.
• Memory Anchor: “Rough ER = ribosomes = exported
proteins.”
Q3. A patient develops severe muscle fatigue after
exposure to cyanide, which inhibits cytochrome oxidase in
mitochondria. Which pathophysiologic consequence best
accounts for the rapid cellular dysfunction?
A. Accumulation of intracellular calcium due to ATP
depletion
B. Increased DNA replication within the nucleus
C. Enhanced lysosomal protein synthesis
D. Excessive sodium extrusion from the cell
