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PATHOPHYSIOLOGY EXAM 1 & FINAL – QUESTIONS
AND ANSWERS WITH RATIONALES
(LATEST VERSION – 2026)
SECTION A: CELLULAR & MOLECULAR PATHOPHYSIOLOGY
Q1. A cell exposed to prolonged hypoxia will FIRST
demonstrate which intracellular change?
A. Nuclear fragmentation
B. Failure of Na⁺/K⁺ ATPase pump
C. Lysosomal membrane rupture
D. DNA denaturation
Answer: B
Rationale: Hypoxia decreases ATP production. ATP depletion
first affects energy-dependent ion pumps, leading to cellular
swelling before irreversible injury occurs.
Q2. Which mechanism BEST explains cellular swelling during
acute injury?
A. Increased protein synthesis
B. Calcium efflux from mitochondria
C. Sodium and water influx
D. Increased lysosomal enzyme activity
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Answer: C
Rationale: Failure of the Na⁺/K⁺ pump allows sodium
accumulation inside the cell, drawing water inward and causing
swelling.
Q3. Apoptosis differs from necrosis because apoptosis:
A. Causes inflammation
B. Is ATP-independent
C. Involves cell membrane rupture
D. Is genetically programmed
Answer: D
Rationale: Apoptosis is a regulated, energy-dependent,
programmed cell death without inflammation.
Q4. Which enzyme is primarily responsible for DNA
fragmentation during apoptosis?
A. Caspase-3
B. Catalase
C. Superoxide dismutase
D. Telomerase
Answer: A
Rationale: Executioner caspases (especially caspase-3) cleave
nuclear proteins and activate DNases.
,3
Q5. Free radical injury is MOST directly caused by:
A. Lipid peroxidation
B. ATP synthesis
C. Protein folding
D. Glucose oxidation
Answer: A
Rationale: Reactive oxygen species attack membrane lipids,
causing loss of membrane integrity.
Q6. Metaplasia is BEST described as:
A. Increased cell number
B. Replacement of one mature cell type with another
C. Uncontrolled cell growth
D. Cellular death
Answer: B
Rationale: Metaplasia is an adaptive response where one
differentiated cell type is replaced by another more resistant
type.
Q7. Dysplasia is clinically significant because it:
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A. Is always reversible
B. Indicates malignant transformation has occurred
C. May progress to cancer
D. Occurs only in epithelial tissue
Answer: C
Rationale: Dysplasia represents disordered growth and is
considered a premalignant change.
Q8. Which intracellular ion MOST directly activates apoptotic
pathways when elevated?
A. Sodium
B. Potassium
C. Calcium
D. Chloride
Answer: C
Rationale: Increased intracellular calcium activates
phospholipases, proteases, and endonucleases.
Q9. The mitochondrial pathway of apoptosis is triggered by:
A. Death receptor binding
B. Cytochrome c release
C. Lysosomal rupture
D. ATP overproduction
PATHOPHYSIOLOGY EXAM 1 & FINAL – QUESTIONS
AND ANSWERS WITH RATIONALES
(LATEST VERSION – 2026)
SECTION A: CELLULAR & MOLECULAR PATHOPHYSIOLOGY
Q1. A cell exposed to prolonged hypoxia will FIRST
demonstrate which intracellular change?
A. Nuclear fragmentation
B. Failure of Na⁺/K⁺ ATPase pump
C. Lysosomal membrane rupture
D. DNA denaturation
Answer: B
Rationale: Hypoxia decreases ATP production. ATP depletion
first affects energy-dependent ion pumps, leading to cellular
swelling before irreversible injury occurs.
Q2. Which mechanism BEST explains cellular swelling during
acute injury?
A. Increased protein synthesis
B. Calcium efflux from mitochondria
C. Sodium and water influx
D. Increased lysosomal enzyme activity
,2
Answer: C
Rationale: Failure of the Na⁺/K⁺ pump allows sodium
accumulation inside the cell, drawing water inward and causing
swelling.
Q3. Apoptosis differs from necrosis because apoptosis:
A. Causes inflammation
B. Is ATP-independent
C. Involves cell membrane rupture
D. Is genetically programmed
Answer: D
Rationale: Apoptosis is a regulated, energy-dependent,
programmed cell death without inflammation.
Q4. Which enzyme is primarily responsible for DNA
fragmentation during apoptosis?
A. Caspase-3
B. Catalase
C. Superoxide dismutase
D. Telomerase
Answer: A
Rationale: Executioner caspases (especially caspase-3) cleave
nuclear proteins and activate DNases.
,3
Q5. Free radical injury is MOST directly caused by:
A. Lipid peroxidation
B. ATP synthesis
C. Protein folding
D. Glucose oxidation
Answer: A
Rationale: Reactive oxygen species attack membrane lipids,
causing loss of membrane integrity.
Q6. Metaplasia is BEST described as:
A. Increased cell number
B. Replacement of one mature cell type with another
C. Uncontrolled cell growth
D. Cellular death
Answer: B
Rationale: Metaplasia is an adaptive response where one
differentiated cell type is replaced by another more resistant
type.
Q7. Dysplasia is clinically significant because it:
, 4
A. Is always reversible
B. Indicates malignant transformation has occurred
C. May progress to cancer
D. Occurs only in epithelial tissue
Answer: C
Rationale: Dysplasia represents disordered growth and is
considered a premalignant change.
Q8. Which intracellular ion MOST directly activates apoptotic
pathways when elevated?
A. Sodium
B. Potassium
C. Calcium
D. Chloride
Answer: C
Rationale: Increased intracellular calcium activates
phospholipases, proteases, and endonucleases.
Q9. The mitochondrial pathway of apoptosis is triggered by:
A. Death receptor binding
B. Cytochrome c release
C. Lysosomal rupture
D. ATP overproduction
