Understanding Pathophysiology
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent bacterial
infections, poor wound healing, and delayed separation of the
umbilical cord after birth. Neutrophil counts are elevated, but
neutrophils fail to accumulate at sites of tissue injury. The
defect most directly involves failure of which cellular process?
A. Integrin-mediated cell-to-cell adhesion
B. Ligand-gated calcium influx
C. Lysosomal enzyme activation
D. Mitochondrial oxidative phosphorylation
E. Ribosomal protein synthesis
Correct Answer: A
,Rationale:
Clinical Clue:
Delayed umbilical cord separation and impaired neutrophil
migration strongly suggest defective leukocyte adhesion.
Mechanism:
Neutrophil extravasation requires integrin-mediated adhesion
between leukocytes and endothelial cells before transmigration
into tissues.
Why the Correct Answer Is Right:
Failure of integrin-dependent adhesion prevents neutrophils
from firmly attaching to endothelium, impairing tissue
migration despite adequate circulating neutrophils.
Why the Other Options Are Wrong:
B. Calcium influx affects signaling but not the primary adhesion
defect.
C. Lysosomal dysfunction impairs killing after migration occurs.
D. Oxidative phosphorylation defects cause energy failure, not
selective migration impairment.
E. Ribosomal defects impair protein synthesis globally.
Exam Trap (common misconception tested):
Confusing elevated neutrophil count with adequate neutrophil
function.
High-Yield Clinical Correlation:
Cell adhesion molecules are essential for immune surveillance,
inflammation, and tissue repair.
,Q2. A hepatocyte exposed to a toxin develops marked swelling
with cytoplasmic vacuolization. ATP levels are significantly
reduced. The earliest pathophysiologic change most likely
involved which membrane transport abnormality?
A. Increased facilitated diffusion of glucose
B. Failure of sodium-potassium ATPase activity
C. Enhanced receptor-mediated endocytosis
D. Increased chloride export
E. Activation of aquaporin-independent transport
Correct Answer: B
Rationale:
Clinical Clue:
Cellular swelling after toxic injury indicates impaired ion
homeostasis.
Mechanism:
ATP depletion disables sodium-potassium ATPase pumps,
allowing intracellular sodium and water accumulation.
Why the Correct Answer Is Right:
Loss of ATP-dependent membrane transport causes osmotic
influx of water, leading to hydropic cellular swelling.
Why the Other Options Are Wrong:
A. Glucose transport does not directly explain generalized
swelling.
C. Endocytosis is not the primary driver of osmotic injury.
, D. Chloride export would not produce marked swelling.
E. Water movement remains largely osmotic.
Exam Trap (common misconception tested):
Assuming cell swelling is caused primarily by membrane
rupture rather than pump failure.
High-Yield Clinical Correlation:
Hydropic change is often the earliest reversible manifestation
of cellular injury.
Q3. A researcher inhibits rough endoplasmic reticulum function
in rapidly dividing plasma cells. Which consequence would most
directly result?
A. Reduced phospholipid synthesis
B. Failure of ATP generation
C. Decreased immunoglobulin production
D. Impaired lysosomal digestion
E. Reduced spindle formation during mitosis
Correct Answer: C
Rationale:
Clinical Clue:
Plasma cells specialize in antibody synthesis.
Mechanism:
Rough endoplasmic reticulum contains ribosome-studded
membranes responsible for synthesis of secreted proteins.
8th Edition
Author(s)Sue E. Huether
TEST BANK
Q1. A 6-year-old boy presents with recurrent bacterial
infections, poor wound healing, and delayed separation of the
umbilical cord after birth. Neutrophil counts are elevated, but
neutrophils fail to accumulate at sites of tissue injury. The
defect most directly involves failure of which cellular process?
A. Integrin-mediated cell-to-cell adhesion
B. Ligand-gated calcium influx
C. Lysosomal enzyme activation
D. Mitochondrial oxidative phosphorylation
E. Ribosomal protein synthesis
Correct Answer: A
,Rationale:
Clinical Clue:
Delayed umbilical cord separation and impaired neutrophil
migration strongly suggest defective leukocyte adhesion.
Mechanism:
Neutrophil extravasation requires integrin-mediated adhesion
between leukocytes and endothelial cells before transmigration
into tissues.
Why the Correct Answer Is Right:
Failure of integrin-dependent adhesion prevents neutrophils
from firmly attaching to endothelium, impairing tissue
migration despite adequate circulating neutrophils.
Why the Other Options Are Wrong:
B. Calcium influx affects signaling but not the primary adhesion
defect.
C. Lysosomal dysfunction impairs killing after migration occurs.
D. Oxidative phosphorylation defects cause energy failure, not
selective migration impairment.
E. Ribosomal defects impair protein synthesis globally.
Exam Trap (common misconception tested):
Confusing elevated neutrophil count with adequate neutrophil
function.
High-Yield Clinical Correlation:
Cell adhesion molecules are essential for immune surveillance,
inflammation, and tissue repair.
,Q2. A hepatocyte exposed to a toxin develops marked swelling
with cytoplasmic vacuolization. ATP levels are significantly
reduced. The earliest pathophysiologic change most likely
involved which membrane transport abnormality?
A. Increased facilitated diffusion of glucose
B. Failure of sodium-potassium ATPase activity
C. Enhanced receptor-mediated endocytosis
D. Increased chloride export
E. Activation of aquaporin-independent transport
Correct Answer: B
Rationale:
Clinical Clue:
Cellular swelling after toxic injury indicates impaired ion
homeostasis.
Mechanism:
ATP depletion disables sodium-potassium ATPase pumps,
allowing intracellular sodium and water accumulation.
Why the Correct Answer Is Right:
Loss of ATP-dependent membrane transport causes osmotic
influx of water, leading to hydropic cellular swelling.
Why the Other Options Are Wrong:
A. Glucose transport does not directly explain generalized
swelling.
C. Endocytosis is not the primary driver of osmotic injury.
, D. Chloride export would not produce marked swelling.
E. Water movement remains largely osmotic.
Exam Trap (common misconception tested):
Assuming cell swelling is caused primarily by membrane
rupture rather than pump failure.
High-Yield Clinical Correlation:
Hydropic change is often the earliest reversible manifestation
of cellular injury.
Q3. A researcher inhibits rough endoplasmic reticulum function
in rapidly dividing plasma cells. Which consequence would most
directly result?
A. Reduced phospholipid synthesis
B. Failure of ATP generation
C. Decreased immunoglobulin production
D. Impaired lysosomal digestion
E. Reduced spindle formation during mitosis
Correct Answer: C
Rationale:
Clinical Clue:
Plasma cells specialize in antibody synthesis.
Mechanism:
Rough endoplasmic reticulum contains ribosome-studded
membranes responsible for synthesis of secreted proteins.
