Understanding Pathophysiology
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent bacterial
infections, delayed wound healing, and marked leukocytosis
despite minimal purulent drainage from infected tissues. Flow
cytometry demonstrates absent expression of a β2-integrin
adhesion molecule on neutrophils. The inability of neutrophils
to migrate into tissues is most directly explained by failure of
which cellular process?
A. Chemokine-mediated actin polymerization
B. Endothelial transcytosis of plasma proteins
C. Firm adhesion between leukocytes and endothelium
D. Fc receptor–mediated phagocytosis
E. Oxidative burst generation within lysosomes
,Correct Answer: C
Rationale:
Clinical Clue:
Recurrent infections with absent pus formation and impaired
neutrophil tissue migration indicate leukocyte adhesion
deficiency.
Mechanism:
β2-integrins mediate stable adhesion of neutrophils to
endothelial ICAM molecules before transmigration.
Why the Correct Answer Is Right:
Firm adhesion is required for neutrophils to exit the circulation.
Loss of integrin-mediated adhesion prevents diapedesis despite
preserved chemotaxis signals.
Why the Other Options Are Wrong:
A. Actin polymerization supports motility but occurs after
adhesion signaling.
B. Endothelial transcytosis concerns fluid and protein
movement, not leukocyte arrest.
D. Fc receptor function affects phagocytosis after tissue entry.
E. Oxidative burst defects cause chronic granulomatous
disease, not migration failure.
Exam Trap (common misconception tested):
Confusing chemotaxis defects with adhesion defects.
,High-Yield Clinical Correlation:
Leukocyte adhesion deficiency commonly presents with
delayed umbilical cord separation and persistent neutrophilia.
Q2. A patient with severe malnutrition develops generalized
edema despite normal cardiac and renal function. Reduced
intracellular synthesis of plasma proteins is primarily occurring
within which organelle?
A. Smooth endoplasmic reticulum
B. Golgi apparatus
C. Lysosome
D. Rough endoplasmic reticulum
E. Peroxisome
Correct Answer: D
Rationale:
Clinical Clue:
Hypoalbuminemia from protein deficiency leads to decreased
plasma oncotic pressure and edema.
Mechanism:
Secreted proteins such as albumin are synthesized by
ribosome-studded rough endoplasmic reticulum.
Why the Correct Answer Is Right:
The rough endoplasmic reticulum is specialized for synthesis of
membrane-bound and secreted proteins.
, Why the Other Options Are Wrong:
A. Smooth ER synthesizes lipids and detoxifies compounds.
B. Golgi modifies and packages proteins after synthesis.
C. Lysosomes digest intracellular debris.
E. Peroxisomes perform oxidative metabolism and fatty acid
breakdown.
Exam Trap (common misconception tested):
Assuming the Golgi apparatus synthesizes proteins rather than
modifies them.
High-Yield Clinical Correlation:
Rough ER dysfunction contributes to diseases involving
defective protein secretion and accumulation of misfolded
proteins.
Q3. A researcher exposes hepatocytes to cyanide, causing
abrupt cessation of oxidative phosphorylation. Which
immediate cellular consequence most directly explains
subsequent membrane pump failure?
A. Excessive ribosomal detachment
B. Depletion of intracellular ATP
C. Increased lysosomal permeability
D. Activation of phospholipase enzymes
E. Fragmentation of Golgi cisternae
Correct Answer: B
Rationale:
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent bacterial
infections, delayed wound healing, and marked leukocytosis
despite minimal purulent drainage from infected tissues. Flow
cytometry demonstrates absent expression of a β2-integrin
adhesion molecule on neutrophils. The inability of neutrophils
to migrate into tissues is most directly explained by failure of
which cellular process?
A. Chemokine-mediated actin polymerization
B. Endothelial transcytosis of plasma proteins
C. Firm adhesion between leukocytes and endothelium
D. Fc receptor–mediated phagocytosis
E. Oxidative burst generation within lysosomes
,Correct Answer: C
Rationale:
Clinical Clue:
Recurrent infections with absent pus formation and impaired
neutrophil tissue migration indicate leukocyte adhesion
deficiency.
Mechanism:
β2-integrins mediate stable adhesion of neutrophils to
endothelial ICAM molecules before transmigration.
Why the Correct Answer Is Right:
Firm adhesion is required for neutrophils to exit the circulation.
Loss of integrin-mediated adhesion prevents diapedesis despite
preserved chemotaxis signals.
Why the Other Options Are Wrong:
A. Actin polymerization supports motility but occurs after
adhesion signaling.
B. Endothelial transcytosis concerns fluid and protein
movement, not leukocyte arrest.
D. Fc receptor function affects phagocytosis after tissue entry.
E. Oxidative burst defects cause chronic granulomatous
disease, not migration failure.
Exam Trap (common misconception tested):
Confusing chemotaxis defects with adhesion defects.
,High-Yield Clinical Correlation:
Leukocyte adhesion deficiency commonly presents with
delayed umbilical cord separation and persistent neutrophilia.
Q2. A patient with severe malnutrition develops generalized
edema despite normal cardiac and renal function. Reduced
intracellular synthesis of plasma proteins is primarily occurring
within which organelle?
A. Smooth endoplasmic reticulum
B. Golgi apparatus
C. Lysosome
D. Rough endoplasmic reticulum
E. Peroxisome
Correct Answer: D
Rationale:
Clinical Clue:
Hypoalbuminemia from protein deficiency leads to decreased
plasma oncotic pressure and edema.
Mechanism:
Secreted proteins such as albumin are synthesized by
ribosome-studded rough endoplasmic reticulum.
Why the Correct Answer Is Right:
The rough endoplasmic reticulum is specialized for synthesis of
membrane-bound and secreted proteins.
, Why the Other Options Are Wrong:
A. Smooth ER synthesizes lipids and detoxifies compounds.
B. Golgi modifies and packages proteins after synthesis.
C. Lysosomes digest intracellular debris.
E. Peroxisomes perform oxidative metabolism and fatty acid
breakdown.
Exam Trap (common misconception tested):
Assuming the Golgi apparatus synthesizes proteins rather than
modifies them.
High-Yield Clinical Correlation:
Rough ER dysfunction contributes to diseases involving
defective protein secretion and accumulation of misfolded
proteins.
Q3. A researcher exposes hepatocytes to cyanide, causing
abrupt cessation of oxidative phosphorylation. Which
immediate cellular consequence most directly explains
subsequent membrane pump failure?
A. Excessive ribosomal detachment
B. Depletion of intracellular ATP
C. Increased lysosomal permeability
D. Activation of phospholipase enzymes
E. Fragmentation of Golgi cisternae
Correct Answer: B
Rationale:
