Pathophysiology – Q&A (2026) PDF | Chamberlain
1. A 55-year-old man with chronic hypertension develops an enlarged heart. This increase in
myocardial muscle mass is primarily due to:
A) Hypertrophy
B) Hyperplasia
C) Metaplasia
D) Dysplasia
Correct Answer: A) Hypertrophy
Rationale: Cardiac muscle cells are terminally differentiated and cannot divide; they respond
to sustained pressure overload by increasing cell size (hypertrophy), not cell number
(hyperplasia). Metaplasia and dysplasia involve changes in cell differentiation or abnormal
growth, not enlargement.
2. The irreversible point in cellular injury at which cell death is inevitable, even if the stressor
is removed, is called the:
A) Necrotic threshold
B) Point of no return
C) Apoptotic switch
D) Ischemic limit
Correct Answer: B) Point of no return
Rationale: The point of no return occurs when mitochondrial damage is so extensive that ATP
synthesis ceases, leading to irreversible membrane and DNA damage. Apoptosis is a
controlled process; necrosis is unregulated but not a threshold term.
,3. Which cellular adaptation involves the replacement of one differentiated cell type with
another that is better suited to withstand stress?
A) Dysplasia
B) Hypertrophy
C) Metaplasia
D) Hyperplasia
Correct Answer: C) Metaplasia
Rationale: Metaplasia is a reversible change where one mature cell type is replaced by
another, such as the transformation of respiratory epithelium in smokers. Dysplasia indicates
disordered growth; hypertrophy and hyperplasia refer to size or number increases.
4. A patient with severe ischemia has reperfusion injury. Which mechanism contributes most
to this additional damage?
A) Activation of apoptosis
B) Accumulation of lactic acid
C) Influx of calcium and generation of oxygen free radicals
D) Decreased mitochondrial biogenesis
Correct Answer: D) Influx of calcium and generation of oxygen free radicals
Rationale: Reperfusion injury is driven by calcium overload and massive production of
reactive oxygen species when blood flow is restored, exacerbating cellular damage. Apoptosis
may occur but is not the primary mechanism of reperfusion injury.
5. The p53 tumor suppressor gene is known as the “guardian of the genome” because it:
A) Promotes cell division
B) Repairs DNA and induces apoptosis if damage is irreparable
, C) Enhances angiogenesis
D) Inhibits immune surveillance
Correct Answer: B) Repairs DNA and induces apoptosis if damage is irreparable
Rationale: p53 arrests the cell cycle to allow DNA repair, and if damage is too severe, it
triggers apoptosis. This prevents propagation of mutations. p53 is frequently mutated in
cancers, illustrating its critical role in tumor suppression.
6. A patient is found to have a mutation in the APC gene. This gene is classified as a:
A) Oncogene
B) Proto-oncogene
C) Tumor suppressor gene
D) Growth factor receptor
Correct Answer: C) Tumor suppressor gene
Rationale: APC (adenomatous polyposis coli) is a tumor suppressor gene; loss of function
leads to uncontrolled cell proliferation, particularly in colorectal cancer. Oncogenes (e.g.,
RAS) and proto-oncogenes promote growth, whereas tumor suppressors inhibit it.
7. The two-hit hypothesis for tumor suppressor genes requires:
A) One mutated allele and one normal allele
B) Both alleles to be inactivated
C) Activation of proto-oncogenes
D) Chromosomal translocation
Correct Answer: D) Both alleles to be inactivated