NUR 631 Final Exam 2026/2027 – Advanced
Physiology & Pathophysiology Questions
and Answers with Rationales
QUESTIONS 1–25: CELLULAR PHYSIOLOGY, HOMEOSTASIS & GENETICS
1. Which mechanism is primarily responsible for maintaining a stable
internal environment?
A. Positive feedback
B. Negative feedback
C. Feed-forward amplification
D. Cellular apoptosis
Answer: B. Negative feedback
Rationale: Negative feedback counteracts deviations from a physiologic
set point and is the major mechanism maintaining homeostasis.
2. Which cellular structure is primarily responsible for ATP
production?
A. Lysosome
B. Golgi apparatus
C. Mitochondrion
D. Ribosome
Answer: C. Mitochondrion
Rationale: Mitochondria generate most cellular ATP through oxidative
phosphorylation.
,3. A patient develops cellular swelling following severe hypoxia.
Which mechanism best explains this finding?
A. Increased protein synthesis
B. Failure of the sodium-potassium pump
C. Increased lysosomal activity
D. Increased DNA replication
Answer: B. Failure of the sodium-potassium pump
Rationale: ATP depletion impairs Na⁺/K⁺-ATPase activity, causing
intracellular sodium and water accumulation.
4. Which process describes programmed, energy-dependent cell
death?
A. Necrosis
B. Apoptosis
C. Autolysis
D. Ischemia
Answer: B. Apoptosis
Rationale: Apoptosis is regulated cell death that generally produces
minimal surrounding inflammation.
5. Which finding is most characteristic of necrosis?
A. Cell shrinkage without inflammation
B. Controlled DNA fragmentation
C. Membrane disruption and inflammation
D. Physiologic elimination of aged cells
Answer: C. Membrane disruption and inflammation
Rationale: Necrosis involves loss of membrane integrity and release of
intracellular contents, provoking inflammation.
6. Which electrolyte is the principal intracellular cation?
,A. Sodium
B. Calcium
C. Potassium
D. Chloride
Answer: C. Potassium
Rationale: Potassium is the major intracellular cation and is essential
for membrane potential and cellular excitability.
7. Which electrolyte is the principal extracellular cation?
A. Potassium
B. Sodium
C. Magnesium
D. Phosphate
Answer: B. Sodium
Rationale: Sodium is the dominant extracellular cation and is important
for extracellular fluid volume and membrane physiology.
8. What is the primary function of the sodium-potassium pump?
A. Move sodium and potassium down concentration gradients
B. Move three sodium ions into cells and two potassium ions out
C. Move three sodium ions out and two potassium ions into cells
D. Exchange calcium for sodium
Answer: C. Move three sodium ions out and two potassium ions into
cells
Rationale: The Na⁺/K⁺-ATPase uses ATP to pump three Na⁺ out and two
K⁺ into the cell.
9. Which cellular adaptation involves an increase in cell size?
A. Hyperplasia
B. Hypertrophy
, C. Atrophy
D. Metaplasia
Answer: B. Hypertrophy
Rationale: Hypertrophy is enlargement of individual cells, often
occurring in skeletal or cardiac muscle.
10. Which cellular adaptation involves an increase in the number of
cells?
A. Hypertrophy
B. Hyperplasia
C. Atrophy
D. Dysplasia
Answer: B. Hyperplasia
Rationale: Hyperplasia is increased cell proliferation and may be
physiologic or pathologic.
11. Metaplasia is best described as:
A. Irreversible malignant transformation
B. Replacement of one mature cell type by another
C. Increased cell size
D. Cellular death from ischemia
Answer: B. Replacement of one mature cell type by another
Rationale: Metaplasia is an adaptive, potentially reversible substitution
of one differentiated cell type for another.
12. Dysplasia is particularly concerning because it:
A. Always represents benign adaptation
B. Is associated with abnormal cellular organization and cancer risk
C. Represents normal tissue maturation
D. Only occurs during childhood
Physiology & Pathophysiology Questions
and Answers with Rationales
QUESTIONS 1–25: CELLULAR PHYSIOLOGY, HOMEOSTASIS & GENETICS
1. Which mechanism is primarily responsible for maintaining a stable
internal environment?
A. Positive feedback
B. Negative feedback
C. Feed-forward amplification
D. Cellular apoptosis
Answer: B. Negative feedback
Rationale: Negative feedback counteracts deviations from a physiologic
set point and is the major mechanism maintaining homeostasis.
2. Which cellular structure is primarily responsible for ATP
production?
A. Lysosome
B. Golgi apparatus
C. Mitochondrion
D. Ribosome
Answer: C. Mitochondrion
Rationale: Mitochondria generate most cellular ATP through oxidative
phosphorylation.
,3. A patient develops cellular swelling following severe hypoxia.
Which mechanism best explains this finding?
A. Increased protein synthesis
B. Failure of the sodium-potassium pump
C. Increased lysosomal activity
D. Increased DNA replication
Answer: B. Failure of the sodium-potassium pump
Rationale: ATP depletion impairs Na⁺/K⁺-ATPase activity, causing
intracellular sodium and water accumulation.
4. Which process describes programmed, energy-dependent cell
death?
A. Necrosis
B. Apoptosis
C. Autolysis
D. Ischemia
Answer: B. Apoptosis
Rationale: Apoptosis is regulated cell death that generally produces
minimal surrounding inflammation.
5. Which finding is most characteristic of necrosis?
A. Cell shrinkage without inflammation
B. Controlled DNA fragmentation
C. Membrane disruption and inflammation
D. Physiologic elimination of aged cells
Answer: C. Membrane disruption and inflammation
Rationale: Necrosis involves loss of membrane integrity and release of
intracellular contents, provoking inflammation.
6. Which electrolyte is the principal intracellular cation?
,A. Sodium
B. Calcium
C. Potassium
D. Chloride
Answer: C. Potassium
Rationale: Potassium is the major intracellular cation and is essential
for membrane potential and cellular excitability.
7. Which electrolyte is the principal extracellular cation?
A. Potassium
B. Sodium
C. Magnesium
D. Phosphate
Answer: B. Sodium
Rationale: Sodium is the dominant extracellular cation and is important
for extracellular fluid volume and membrane physiology.
8. What is the primary function of the sodium-potassium pump?
A. Move sodium and potassium down concentration gradients
B. Move three sodium ions into cells and two potassium ions out
C. Move three sodium ions out and two potassium ions into cells
D. Exchange calcium for sodium
Answer: C. Move three sodium ions out and two potassium ions into
cells
Rationale: The Na⁺/K⁺-ATPase uses ATP to pump three Na⁺ out and two
K⁺ into the cell.
9. Which cellular adaptation involves an increase in cell size?
A. Hyperplasia
B. Hypertrophy
, C. Atrophy
D. Metaplasia
Answer: B. Hypertrophy
Rationale: Hypertrophy is enlargement of individual cells, often
occurring in skeletal or cardiac muscle.
10. Which cellular adaptation involves an increase in the number of
cells?
A. Hypertrophy
B. Hyperplasia
C. Atrophy
D. Dysplasia
Answer: B. Hyperplasia
Rationale: Hyperplasia is increased cell proliferation and may be
physiologic or pathologic.
11. Metaplasia is best described as:
A. Irreversible malignant transformation
B. Replacement of one mature cell type by another
C. Increased cell size
D. Cellular death from ischemia
Answer: B. Replacement of one mature cell type by another
Rationale: Metaplasia is an adaptive, potentially reversible substitution
of one differentiated cell type for another.
12. Dysplasia is particularly concerning because it:
A. Always represents benign adaptation
B. Is associated with abnormal cellular organization and cancer risk
C. Represents normal tissue maturation
D. Only occurs during childhood
