Understanding Pathophysiology
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old child presents with recurrent bacterial
infections, delayed wound healing, and poor leukocyte
migration into infected tissue despite marked neutrophilia on
laboratory evaluation. Flow cytometry demonstrates absence
of β2-integrin expression on neutrophils. The inability of
neutrophils to localize to sites of infection is most directly
explained by failure of which cellular process?
A. Chemokine synthesis within endothelial cells
B. Firm adhesion between leukocytes and vascular endothelium
C. Histamine-mediated vasodilation of postcapillary venules
D. Opsonization of bacteria by immunoglobulin G
E. Margination caused by reduced blood flow velocity
,Correct Answer: B
Rationale:
Clinical Clue:
Recurrent infections with impaired neutrophil tissue migration
despite neutrophilia indicates defective leukocyte adhesion.
Mechanism:
β2-integrins mediate firm leukocyte adhesion to endothelial
ICAM molecules before transmigration.
Why the Correct Answer Is Right:
Without integrin-mediated adhesion, leukocytes cannot firmly
attach to endothelium and therefore fail to undergo diapedesis
into tissues.
Why the Other Options Are Wrong:
A. Chemokines remain functional and initiate rolling/activation.
C. Vasodilation occurs independently of integrin expression.
D. Opsonization enhances phagocytosis, not endothelial
attachment.
E. Margination precedes firm adhesion and is not the primary
defect.
Exam Trap (common misconception tested):
Confusing leukocyte rolling with firm adhesion.
High-Yield Clinical Correlation:
Leukocyte adhesion defects produce severe bacterial infections
with delayed separation of the umbilical cord and absent pus
formation.
,Q2. A researcher inhibits mitochondrial oxidative
phosphorylation in cultured skeletal muscle cells. Within
minutes, intracellular ATP levels fall substantially. Which
cellular function would be impaired first?
A. DNA transcription
B. Protein synthesis in the rough endoplasmic reticulum
C. Maintenance of transmembrane sodium and potassium
gradients
D. Lysosomal degradation of intracellular debris
E. Steroid hormone synthesis
Correct Answer: C
Rationale:
Clinical Clue:
Acute ATP depletion rapidly affects energy-dependent
membrane transport.
Mechanism:
The Na+/K+-ATPase requires continuous ATP hydrolysis to
preserve ionic gradients.
Why the Correct Answer Is Right:
Failure of sodium-potassium transport occurs early in ATP
depletion, causing cellular swelling and membrane dysfunction.
Why the Other Options Are Wrong:
A. Transcription declines later.
, B. Protein synthesis decreases after broader energy failure
develops.
D. Lysosomal degradation is less immediately ATP-sensitive.
E. Steroid synthesis is not the earliest critical ATP-dependent
failure.
Exam Trap (common misconception tested):
Assuming biosynthetic processes fail before membrane
transport systems.
High-Yield Clinical Correlation:
Early ischemic injury is characterized by ATP depletion and
cellular swelling from ion pump failure.
Q3. A patient with chronic alcohol use develops hepatocyte
enlargement due to proliferation of smooth endoplasmic
reticulum (SER). This adaptation most likely reflects increased
demand for which cellular function?
A. Oxidative phosphorylation
B. Intracellular digestion
C. Lipid and drug metabolism
D. Ribosomal protein assembly
E. Chromosomal segregation during mitosis
Correct Answer: C
Rationale:
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old child presents with recurrent bacterial
infections, delayed wound healing, and poor leukocyte
migration into infected tissue despite marked neutrophilia on
laboratory evaluation. Flow cytometry demonstrates absence
of β2-integrin expression on neutrophils. The inability of
neutrophils to localize to sites of infection is most directly
explained by failure of which cellular process?
A. Chemokine synthesis within endothelial cells
B. Firm adhesion between leukocytes and vascular endothelium
C. Histamine-mediated vasodilation of postcapillary venules
D. Opsonization of bacteria by immunoglobulin G
E. Margination caused by reduced blood flow velocity
,Correct Answer: B
Rationale:
Clinical Clue:
Recurrent infections with impaired neutrophil tissue migration
despite neutrophilia indicates defective leukocyte adhesion.
Mechanism:
β2-integrins mediate firm leukocyte adhesion to endothelial
ICAM molecules before transmigration.
Why the Correct Answer Is Right:
Without integrin-mediated adhesion, leukocytes cannot firmly
attach to endothelium and therefore fail to undergo diapedesis
into tissues.
Why the Other Options Are Wrong:
A. Chemokines remain functional and initiate rolling/activation.
C. Vasodilation occurs independently of integrin expression.
D. Opsonization enhances phagocytosis, not endothelial
attachment.
E. Margination precedes firm adhesion and is not the primary
defect.
Exam Trap (common misconception tested):
Confusing leukocyte rolling with firm adhesion.
High-Yield Clinical Correlation:
Leukocyte adhesion defects produce severe bacterial infections
with delayed separation of the umbilical cord and absent pus
formation.
,Q2. A researcher inhibits mitochondrial oxidative
phosphorylation in cultured skeletal muscle cells. Within
minutes, intracellular ATP levels fall substantially. Which
cellular function would be impaired first?
A. DNA transcription
B. Protein synthesis in the rough endoplasmic reticulum
C. Maintenance of transmembrane sodium and potassium
gradients
D. Lysosomal degradation of intracellular debris
E. Steroid hormone synthesis
Correct Answer: C
Rationale:
Clinical Clue:
Acute ATP depletion rapidly affects energy-dependent
membrane transport.
Mechanism:
The Na+/K+-ATPase requires continuous ATP hydrolysis to
preserve ionic gradients.
Why the Correct Answer Is Right:
Failure of sodium-potassium transport occurs early in ATP
depletion, causing cellular swelling and membrane dysfunction.
Why the Other Options Are Wrong:
A. Transcription declines later.
, B. Protein synthesis decreases after broader energy failure
develops.
D. Lysosomal degradation is less immediately ATP-sensitive.
E. Steroid synthesis is not the earliest critical ATP-dependent
failure.
Exam Trap (common misconception tested):
Assuming biosynthetic processes fail before membrane
transport systems.
High-Yield Clinical Correlation:
Early ischemic injury is characterized by ATP depletion and
cellular swelling from ion pump failure.
Q3. A patient with chronic alcohol use develops hepatocyte
enlargement due to proliferation of smooth endoplasmic
reticulum (SER). This adaptation most likely reflects increased
demand for which cellular function?
A. Oxidative phosphorylation
B. Intracellular digestion
C. Lipid and drug metabolism
D. Ribosomal protein assembly
E. Chromosomal segregation during mitosis
Correct Answer: C
Rationale:
