NUR 631 Midterm Exam 2026/2027 – Advanced Physiology &
Pathophysiology | Complete Questions & Verified Answers
with Rationales
Cellular Physiology, Injury, Adaptation & Genetics
1. A patient develops tissue ischemia after an arterial occlusion. Which cellular
change occurs earliest as ATP production declines?
A. Increased oxidative phosphorylation
B. Failure of the sodium-potassium pump
C. Increased protein synthesis
D. Increased intracellular calcium extrusion
Answer: B
Rationale: ATP depletion impairs the Na⁺/K⁺-ATPase, causing intracellular sodium
and water accumulation. This produces cellular swelling and is an early,
potentially reversible manifestation of ischemic injury.
2. Which cellular process is most directly associated with programmed, energy-
dependent cell death?
A. Necrosis
B. Apoptosis
C. Autolysis
D. Coagulation
Answer: B
Rationale: Apoptosis is regulated cell death involving caspase activation, DNA
fragmentation, and cellular dismantling without the intense inflammatory
response typically associated with necrosis.
,3. Which finding most strongly distinguishes necrosis from apoptosis?
A. Activation of intracellular enzymes
B. DNA fragmentation
C. Cellular membrane rupture with inflammation
D. Caspase activation
Answer: C
Rationale: Necrosis commonly involves loss of membrane integrity, leakage of
intracellular contents, and inflammation. Apoptosis generally preserves
membrane integrity until cellular fragments are removed.
4. A patient with chronic gastroesophageal reflux develops replacement of
normal esophageal squamous epithelium with columnar epithelium. This
represents:
A. Hypertrophy
B. Hyperplasia
C. Metaplasia
D. Dysplasia
Answer: C
Rationale: Metaplasia is a reversible adaptation in which one mature
differentiated cell type is replaced by another better suited to the chronic stress.
5. Which cellular adaptation involves an increase in cell size rather than cell
number?
A. Hyperplasia
B. Hypertrophy
C. Metaplasia
D. Dysplasia
Answer: B
,Rationale: Hypertrophy increases individual cell size. Hyperplasia increases cell
number.
6. Which mechanism is primarily responsible for cellular swelling during
reversible injury?
A. Increased intracellular potassium
B. Failure of ATP-dependent ion transport
C. Increased mitochondrial ATP synthesis
D. Increased protein degradation
Answer: B
Rationale: Loss of ATP impairs membrane ion pumps, especially the Na⁺/K⁺-
ATPase. Sodium and water move into cells, producing hydropic swelling.
7. Reactive oxygen species can cause cellular injury primarily by:
A. Increasing membrane stability
B. Promoting lipid peroxidation
C. Increasing ATP production
D. Preventing DNA damage
Answer: B
Rationale: Reactive oxygen species can oxidize membrane lipids, proteins, and
nucleic acids, contributing to cellular dysfunction and death.
8. Which organelle is particularly vulnerable to calcium-mediated injury?
A. Mitochondrion
B. Golgi apparatus only
C. Nucleus only
D. Ribosome
Answer: A
, Rationale: Excess intracellular calcium activates destructive enzymes and can
impair mitochondrial function, worsening ATP depletion and promoting cell
death.
9. A tumor suppressor gene normally contributes to cancer prevention by:
A. Stimulating unrestricted cellular proliferation
B. Promoting DNA damage
C. Restricting inappropriate cell-cycle progression
D. Preventing apoptosis
Answer: C
Rationale: Tumor suppressor proteins regulate cell-cycle checkpoints, DNA repair,
and apoptosis. Loss of their function can permit abnormal proliferation.
10. An activating mutation in a proto-oncogene can result in:
A. Suppression of proliferation
B. Persistent growth signaling
C. Increased apoptosis
D. Reduced cellular survival
Answer: B
Rationale: Proto-oncogenes normally participate in regulated growth signaling.
Activating mutations can convert them into oncogenes that promote persistent
proliferation.
11. Which process describes a heritable change in gene expression that does not
require alteration of the DNA nucleotide sequence?
A. Epigenetic regulation
B. Translation
C. Transcriptional mutation
D. Aneuploidy
Pathophysiology | Complete Questions & Verified Answers
with Rationales
Cellular Physiology, Injury, Adaptation & Genetics
1. A patient develops tissue ischemia after an arterial occlusion. Which cellular
change occurs earliest as ATP production declines?
A. Increased oxidative phosphorylation
B. Failure of the sodium-potassium pump
C. Increased protein synthesis
D. Increased intracellular calcium extrusion
Answer: B
Rationale: ATP depletion impairs the Na⁺/K⁺-ATPase, causing intracellular sodium
and water accumulation. This produces cellular swelling and is an early,
potentially reversible manifestation of ischemic injury.
2. Which cellular process is most directly associated with programmed, energy-
dependent cell death?
A. Necrosis
B. Apoptosis
C. Autolysis
D. Coagulation
Answer: B
Rationale: Apoptosis is regulated cell death involving caspase activation, DNA
fragmentation, and cellular dismantling without the intense inflammatory
response typically associated with necrosis.
,3. Which finding most strongly distinguishes necrosis from apoptosis?
A. Activation of intracellular enzymes
B. DNA fragmentation
C. Cellular membrane rupture with inflammation
D. Caspase activation
Answer: C
Rationale: Necrosis commonly involves loss of membrane integrity, leakage of
intracellular contents, and inflammation. Apoptosis generally preserves
membrane integrity until cellular fragments are removed.
4. A patient with chronic gastroesophageal reflux develops replacement of
normal esophageal squamous epithelium with columnar epithelium. This
represents:
A. Hypertrophy
B. Hyperplasia
C. Metaplasia
D. Dysplasia
Answer: C
Rationale: Metaplasia is a reversible adaptation in which one mature
differentiated cell type is replaced by another better suited to the chronic stress.
5. Which cellular adaptation involves an increase in cell size rather than cell
number?
A. Hyperplasia
B. Hypertrophy
C. Metaplasia
D. Dysplasia
Answer: B
,Rationale: Hypertrophy increases individual cell size. Hyperplasia increases cell
number.
6. Which mechanism is primarily responsible for cellular swelling during
reversible injury?
A. Increased intracellular potassium
B. Failure of ATP-dependent ion transport
C. Increased mitochondrial ATP synthesis
D. Increased protein degradation
Answer: B
Rationale: Loss of ATP impairs membrane ion pumps, especially the Na⁺/K⁺-
ATPase. Sodium and water move into cells, producing hydropic swelling.
7. Reactive oxygen species can cause cellular injury primarily by:
A. Increasing membrane stability
B. Promoting lipid peroxidation
C. Increasing ATP production
D. Preventing DNA damage
Answer: B
Rationale: Reactive oxygen species can oxidize membrane lipids, proteins, and
nucleic acids, contributing to cellular dysfunction and death.
8. Which organelle is particularly vulnerable to calcium-mediated injury?
A. Mitochondrion
B. Golgi apparatus only
C. Nucleus only
D. Ribosome
Answer: A
, Rationale: Excess intracellular calcium activates destructive enzymes and can
impair mitochondrial function, worsening ATP depletion and promoting cell
death.
9. A tumor suppressor gene normally contributes to cancer prevention by:
A. Stimulating unrestricted cellular proliferation
B. Promoting DNA damage
C. Restricting inappropriate cell-cycle progression
D. Preventing apoptosis
Answer: C
Rationale: Tumor suppressor proteins regulate cell-cycle checkpoints, DNA repair,
and apoptosis. Loss of their function can permit abnormal proliferation.
10. An activating mutation in a proto-oncogene can result in:
A. Suppression of proliferation
B. Persistent growth signaling
C. Increased apoptosis
D. Reduced cellular survival
Answer: B
Rationale: Proto-oncogenes normally participate in regulated growth signaling.
Activating mutations can convert them into oncogenes that promote persistent
proliferation.
11. Which process describes a heritable change in gene expression that does not
require alteration of the DNA nucleotide sequence?
A. Epigenetic regulation
B. Translation
C. Transcriptional mutation
D. Aneuploidy
