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 boy presents with recurrent sinopulmonary
infections and chronic diarrhea. Electron microscopy of
respiratory epithelial cells demonstrates absent dynein arms
within cilia. The impaired cellular function most directly reflects
disruption of which process?
A. ATP generation within smooth endoplasmic reticulum
B. Cytoskeletal motor protein–dependent intracellular
movement
,C. Oxidative phosphorylation across mitochondrial cristae
D. Ribosomal assembly within the nucleolus
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent respiratory infections with
defective ciliary motility suggests primary ciliary
dyskinesia.
• Mechanism: Dynein arms are ATP-dependent motor
proteins associated with microtubules that permit ciliary
beating.
• Why the Correct Answer Is Right: Loss of dynein impairs
coordinated movement of cilia and intracellular transport
along microtubules.
• Why the Other Options Are Wrong:
o A: Smooth ER primarily synthesizes lipids and
detoxifies compounds.
o C: Mitochondrial oxidative phosphorylation is not the
primary defect described.
o D: Nucleolar ribosomal assembly does not regulate
ciliary motion.
• Exam Trap: Confusing cytoskeletal motor proteins with
energy production defects.
, • High-Yield Clinical Correlation: Dynein dysfunction can also
impair sperm motility and predispose to infertility.
• Memory Anchor: “Dynein drives.”
Q2. A researcher exposes cultured hepatocytes to a toxin that
selectively disrupts Golgi apparatus function. Which cellular
abnormality would most likely result?
A. Failure of posttranslational protein modification and
packaging
B. Impaired ATP synthesis from fatty acid oxidation
C. Loss of chromosomal replication fidelity
D. Inability to generate messenger RNA transcripts
Correct Answer: A
Rationale:
• Clinical Clue: Golgi disruption classically affects protein
processing and trafficking.
• Mechanism: The Golgi apparatus modifies, sorts, and
packages proteins for secretion or membrane insertion.
• Why the Correct Answer Is Right: Secretory proteins
require Golgi-mediated glycosylation and vesicular
transport.
• Why the Other Options Are Wrong:
o B: Fatty acid oxidation occurs mainly in mitochondria.
, o C: DNA replication occurs in the nucleus.
o D: mRNA transcription is nuclear.
• Exam Trap: Confusing rough ER synthesis with Golgi
packaging.
• High-Yield Clinical Correlation: Many inherited
glycosylation disorders arise from Golgi-processing
defects.
• Memory Anchor: “Golgi ships the package.”
Q3. A patient with severe dehydration develops hypernatremia.
Neurons compensate by increasing intracellular osmolyte
concentration. Water movement into these cells occurs
primarily through which mechanism?
A. Facilitated diffusion through carrier proteins
B. Active transport using ATP hydrolysis
C. Osmosis across semipermeable membranes
D. Endocytosis through clathrin-coated vesicles
Correct Answer: C
Rationale:
• Clinical Clue: Hypernatremia alters osmotic gradients
across cell membranes.
• Mechanism: Water moves passively toward areas of higher
solute concentration.
The Biologic Basis for Disease in Adults
and Children
9th Edition
Author(s)Julia Rogers
TEST BANK
Q1. A 6-year-old boy presents with recurrent sinopulmonary
infections and chronic diarrhea. Electron microscopy of
respiratory epithelial cells demonstrates absent dynein arms
within cilia. The impaired cellular function most directly reflects
disruption of which process?
A. ATP generation within smooth endoplasmic reticulum
B. Cytoskeletal motor protein–dependent intracellular
movement
,C. Oxidative phosphorylation across mitochondrial cristae
D. Ribosomal assembly within the nucleolus
Correct Answer: B
Rationale:
• Clinical Clue: Recurrent respiratory infections with
defective ciliary motility suggests primary ciliary
dyskinesia.
• Mechanism: Dynein arms are ATP-dependent motor
proteins associated with microtubules that permit ciliary
beating.
• Why the Correct Answer Is Right: Loss of dynein impairs
coordinated movement of cilia and intracellular transport
along microtubules.
• Why the Other Options Are Wrong:
o A: Smooth ER primarily synthesizes lipids and
detoxifies compounds.
o C: Mitochondrial oxidative phosphorylation is not the
primary defect described.
o D: Nucleolar ribosomal assembly does not regulate
ciliary motion.
• Exam Trap: Confusing cytoskeletal motor proteins with
energy production defects.
, • High-Yield Clinical Correlation: Dynein dysfunction can also
impair sperm motility and predispose to infertility.
• Memory Anchor: “Dynein drives.”
Q2. A researcher exposes cultured hepatocytes to a toxin that
selectively disrupts Golgi apparatus function. Which cellular
abnormality would most likely result?
A. Failure of posttranslational protein modification and
packaging
B. Impaired ATP synthesis from fatty acid oxidation
C. Loss of chromosomal replication fidelity
D. Inability to generate messenger RNA transcripts
Correct Answer: A
Rationale:
• Clinical Clue: Golgi disruption classically affects protein
processing and trafficking.
• Mechanism: The Golgi apparatus modifies, sorts, and
packages proteins for secretion or membrane insertion.
• Why the Correct Answer Is Right: Secretory proteins
require Golgi-mediated glycosylation and vesicular
transport.
• Why the Other Options Are Wrong:
o B: Fatty acid oxidation occurs mainly in mitochondria.
, o C: DNA replication occurs in the nucleus.
o D: mRNA transcription is nuclear.
• Exam Trap: Confusing rough ER synthesis with Golgi
packaging.
• High-Yield Clinical Correlation: Many inherited
glycosylation disorders arise from Golgi-processing
defects.
• Memory Anchor: “Golgi ships the package.”
Q3. A patient with severe dehydration develops hypernatremia.
Neurons compensate by increasing intracellular osmolyte
concentration. Water movement into these cells occurs
primarily through which mechanism?
A. Facilitated diffusion through carrier proteins
B. Active transport using ATP hydrolysis
C. Osmosis across semipermeable membranes
D. Endocytosis through clathrin-coated vesicles
Correct Answer: C
Rationale:
• Clinical Clue: Hypernatremia alters osmotic gradients
across cell membranes.
• Mechanism: Water moves passively toward areas of higher
solute concentration.
