2025/2026 | Actual Real Exam Questions
and Answers | Objective Assessment ,
provide 200 questions and answers
solutions and rationales
Cellular & Molecular Foundations
1. Which cellular adaptation is characterized by a decrease in cell size due to decreased
workload?
A) Hypertrophy B) Hyperplasia C) Atrophy D) Metaplasia
Answer: C. Atrophy. Rationale: Atrophy is decreased cell size from reduced workload,
nutrition, or stimulation.
2. Reversible cell injury most commonly leads to which microscopic change first?
A) Pyknosis B) Cellular swelling C) Karyorrhexis D) Fibrosis
Answer: B. Cellular swelling. Rationale: Loss of ionic gradients causes water influx
and swelling as an early reversible injury sign.
3. Which process describes replacement of one mature cell type by another better suited to
stress?
A) Dysplasia B) Metaplasia C) Hyperplasia D) Apoptosis
Answer: B. Metaplasia. Rationale: Metaplasia is adaptive substitution of one
differentiated cell type for another.
4. Necrosis differs from apoptosis because necrosis typically:
A) Is energy-dependent B) Causes inflammation C) Is programmed D) Produces
apoptotic bodies
Answer: B. Causes inflammation. Rationale: Necrosis disrupts membranes and elicits
inflammation; apoptosis is noninflammatory.
,5. The hallmark of mitochondrial injury in ischemia is failure of:
A) Glycolysis B) Oxidative phosphorylation C) Protein synthesis D) Lysosomal digestion
Answer: B. Oxidative phosphorylation. Rationale: Ischemia impairs
oxygen-dependent ATP production in mitochondria.
6. Free radical injury primarily damages cells by:
A) Protein phosphorylation B) Lipid peroxidation C) Increasing pH D) Stabilizing
membranes
Answer: B. Lipid peroxidation. Rationale: Free radicals attack membrane lipids
causing peroxidation and membrane dysfunction.
7. Which ion accumulation is central to ischemic cell swelling?
A) Na+ B) K+ C) Ca2+ D) Cl-
Answer: A. Na+. Rationale: Na+/K+ pump failure leads to intracellular Na+
accumulation and water influx.
8. Which is a programmed mechanism of cell death important in embryogenesis?
A) Oncosis B) Apoptosis C) Coagulative necrosis D) Liquefactive necrosis
Answer: B. Apoptosis. Rationale: Apoptosis is regulated cell death essential in
development and tissue homeostasis.
9. A persistent injurious stimulus that causes an adaptive increase in cell number is:
A) Hypertrophy B) Hyperplasia C) Dysplasia D) Atrophy
Answer: B. Hyperplasia. Rationale: Hyperplasia is increased cell number in response
to a stimulus (e.g., hormones).
10.Which change is characteristic of irreversible cell injury?
A) Mitochondrial swelling B) Membrane rupture C) Chromatin clumping reversible D)
Ribosomal detachment reversible
Answer: B. Membrane rupture. Rationale: Loss of membrane integrity means
irreversible injury and necrosis.
11.Which biochemical event triggers apoptosis?
A) Increased ATP B) Cytochrome c release from mitochondria C) Membrane
stabilization D) Lysosomal release
Answer: B. Cytochrome c release. Rationale: Cytochrome c activates caspases
initiating apoptosis.
12.Fatty change in the liver (steatosis) is most commonly due to:
A) Viral infection B) Disordered lipid metabolism C) Autophagy D) Hemorrhage
Answer: B. Disordered lipid metabolism. Rationale: Alcohol, obesity, or toxins disrupt
lipid handling causing steatosis.
, 13.Which organelle is central to intracellular calcium homeostasis?
A) Mitochondria and endoplasmic reticulum B) Golgi apparatus C) Lysosome D)
Nucleus
Answer: A. Mitochondria and ER. Rationale: ER and mitochondria buffer Ca2+;
overload triggers injury and apoptosis.
14.Which form of necrosis is typical of ischemic infarcts in solid organs (kidney, heart)?
A) Caseous B) Coagulative C) Liquefactive D) Fat
Answer: B. Coagulative. Rationale: Coagulative necrosis preserves tissue architecture
initially, typical of infarcts.
15.Hydrogen peroxide and hydroxyl radicals are examples of:
A) Antioxidants B) Reactive oxygen species (ROS) C) Lipids D) Cytokines
Answer: B. Reactive oxygen species. Rationale: ROS cause oxidative damage to
macromolecules.
16.Which mechanism best describes cellular swelling?
A) Increased protein synthesis B) Osmotic changes from ion pump failure C) Increased
apoptosis D) Collagen deposition
Answer: B. Osmotic changes from ion pump failure. Rationale: ATP depletion leads
to pump failure and osmotic water influx.
17.Which histologic feature indicates acute inflammation?
A) Fibrosis B) Neutrophilic infiltration C) Granuloma formation D) Lymphocyte
predominance
Answer: B. Neutrophilic infiltration. Rationale: Neutrophils are the first cells in acute
inflammation.
18.A cell with dysplasia is at increased risk for:
A) Necrosis B) Malignant transformation C) Hypertrophy D) Normalization without risk
Answer: B. Malignant transformation. Rationale: Dysplasia involves atypical cells and
is a precursor to malignancy.
19.Endoplasmic reticulum stress often leads to:
A) Increased protein folding capacity B) Unfolded protein response and possibly
apoptosis C) Increased oxidative phosphorylation D) Lysosomal stabilization
Answer: B. Unfolded protein response and possibly apoptosis. Rationale: ER
stress triggers UPR; prolonged stress triggers apoptosis.
20.Cellular senescence is best described as:
A) Programmed proliferation B) Irreversible cell cycle arrest with secretory phenotype C)
Rapid cell division D) Necrotic death
Answer: B. Irreversible cell cycle arrest with secretory phenotype. Rationale: