, CHAPTER LIST
Chapter 1: Cell Adaptation, Injury, Death, and Aging
Chapter 2: Inflammation and Repair
Chapter 3: Immunopathology
Chapter 4: Neoplasia
Chapter 5: Developmental and Genetic Diseases
Chapter 6: Infectious and Parasitic Diseases
Chapter 7: The Amyloidoses
Chapter 8: Blood Vessels and Hemodynamic Disorders
Chapter 9: Heart
Chapter 10: The Respiratory System
Chapter 11: The Gastrointestinal Tract
Chapter 12: The Liver and Biliary System
Chapter 13: The Exocrine Pancreas
Chapter 14: The Kidney
Chapter 15: The Lower Urinary Tract and Male Reproductive System
Chapter 16: The Female Reproductive Tract
Chapter 17: The Breast
Chapter 18: Hematopathology
Chapter 19: Endocrine System, Diabetes, and Nutritional Diseases
Chapter 20: The Skin
Chapter 21: The Head and Neck
Chapter 22: Bones, Joints, and Soft Tissue
Chapter 23: Skeletal Muscle
Chapter 24: The Central Nervous System and Eye
Chapter 25: Traumatic and Environmental Injury
,Chapter 1: Cell Adaptation, Injury, Death, and
Aging — Test Bank (20 Advanced MCQs)
1) Cellular adaptation to increased workload
A 28-year-old athlete develops increased left ventricular wall thickness after
months of endurance training. Cardiomyocytes show enlarged cell size without
increased cell number. Which molecular change most directly drives this
adaptation?
A. Increased cyclin D expression causing G1→S transition
B. Upregulation of fetal gene program with increased protein synthesis
C. Activation of telomerase with chromosomal stabilization
D. Increased DNA replication with polyploidy
Answer: B
Deep rationale: Mature cardiomyocytes have minimal proliferative capacity, so
increased workload triggers hypertrophy, not hyperplasia. Hypertrophy is
mediated by mechanosensors and growth factor signaling (e.g., IGF-1), leading
to increased protein synthesis, sarcomere remodeling, and re-expression of a
fetal gene program (e.g., β-myosin heavy chain). Cyclin-driven cell cycle entry
is not the principal mechanism here, telomerase activation relates to replicative
aging, and polyploidy may occur in some tissues but is not the core driver of
physiologic cardiac hypertrophy.
Key words: hypertrophy, fetal gene program, cardiomyocyte, protein synthesis
2) Pathologic hypertrophy signaling
A 62-year-old with long-standing hypertension develops concentric left
ventricular hypertrophy. Which signaling pathway is most associated with
pathologic hypertrophy and eventual maladaptive remodeling?
A. PI3K–Akt (physiologic growth)
B. Gq-coupled receptor signaling leading to calcineurin–NFAT activation
C. p53-mediated apoptosis due to DNA damage
D. HIF-1α stabilization due to hypoxia
,Answer: B
Deep rationale: Pathologic hypertrophy commonly results from pressure
overload and neurohumoral stimulation (angiotensin II, endothelin,
catecholamines), which activates Gq-coupled receptors, increasing
intracellular Ca²⁺ and stimulating calcineurin–NFAT transcriptional
responses. This drives maladaptive gene expression, fibrosis, and risk of heart
failure. PI3K–Akt is classically linked to more physiologic hypertrophy. p53 and
HIF-1α can be involved in injury contexts but are not the main hypertrophic
program linked to pressure-overload remodeling.
Key words: pressure overload, calcineurin, NFAT, Gq, maladaptive remodeling
3) Hyperplasia vs hypertrophy
A patient with benign prostatic enlargement has increased organ size due to
increased number of glandular cells. Which statement best explains why this
process is possible in the prostate but not in adult cardiac muscle?
A. Prostate cells have more mitochondria than cardiomyocytes
B. Prostate has a cell population capable of entering the cell cycle;
cardiomyocytes are largely post-mitotic
C. Prostate cells rely on anaerobic metabolism; cardiomyocytes do not
D. Prostate cells do not undergo apoptosis; cardiomyocytes do
Answer: B
Deep rationale: Hyperplasia requires cells capable of proliferation
(stem/progenitor cells or differentiated cells that can re-enter the cycle). The
prostate retains cells responsive to hormonal growth signals (androgen-driven),
enabling increased cell number. Adult cardiomyocytes are terminally
differentiated with minimal regenerative capacity, so they adapt mainly by
hypertrophy. Metabolic and apoptosis differences do not explain the
fundamental capacity for hyperplasia.
Key words: hyperplasia, post-mitotic cells, prostate, regenerative capacity
4) Atrophy mechanism
A 72-year-old with prolonged immobilization after a hip fracture develops
marked quadriceps wasting. Which intracellular process most directly mediates
the reduction in cell size?
A. Increased glycolysis
B. Lysosomal storage of lipofuscin
,C. Ubiquitin–proteasome–mediated protein degradation
D. Increased telomerase activity
Answer: C
Deep rationale: Disuse atrophy is driven by decreased protein synthesis and
increased protein breakdown, especially via the ubiquitin–proteasome
pathway. Autophagy can also contribute, but proteasomal degradation is a key
mechanism for rapid loss of myofibrillar proteins. Lipofuscin is an aging
pigment, telomerase relates to replicative senescence, and glycolysis is not the
primary driver of atrophic protein loss.
Key words: disuse atrophy, ubiquitin-proteasome, protein degradation,
immobilization
5) Metaplasia and risk
A 48-year-old with long-standing gastroesophageal reflux develops intestinal-
type epithelium in the distal esophagus. Which best explains why this adaptive
change can increase cancer risk over time?
A. Metaplasia permanently prevents DNA damage
B. The replacement epithelium is more sensitive to acid injury
C. Persistent stress and inflammatory signaling increase proliferation, raising
mutation accumulation risk
D. Metaplasia is a form of apoptosis
Answer: C
Deep rationale: Metaplasia is a reversible adaptive substitution of one
differentiated cell type for another better suited to the stress environment.
However, chronic injury and inflammation can drive ongoing cell turnover
and proliferative signaling, increasing opportunities for genetic/epigenetic
alterations, progression to dysplasia, and carcinoma. Metaplasia does not
prevent DNA damage, and it is not apoptosis; the new epithelium is often more
resistant to the original stressor, not more sensitive.
Key words: metaplasia, Barrett esophagus, dysplasia, chronic inflammation,
carcinogenesis
6) Reversible injury hallmark
During transient myocardial ischemia, cardiomyocytes show swelling and
membrane blebs, but recover fully after reperfusion within minutes. Which
change most directly causes this reversible cell swelling?
,A. Increased intracellular calcium from ER rupture
B. ATP depletion leading to failure of Na⁺/K⁺-ATPase
C. Lysosomal membrane rupture with enzyme release
D. DNA fragmentation by endonucleases
Answer: B
Deep rationale: Early reversible injury is dominated by ATP depletion due to
impaired oxidative phosphorylation. ATP depletion causes failure of the Na⁺/K⁺-
ATPase, leading to Na⁺ and water influx → cell swelling (hydropic change),
plus membrane blebbing and ER dilation. Lysosomal rupture and DNA
fragmentation are associated with irreversible injury/cell death.
Key words: reversible injury, hydropic change, ATP depletion, Na/K pump,
ischemia
7) Transition to irreversible injury
A tissue experiences prolonged ischemia. Which event most strongly indicates
the injury has become irreversible?
A. Cellular swelling
B. Fatty change
C. Severe mitochondrial dysfunction with inability to restore ATP production
and membrane integrity
D. Ribosome detachment from rough ER
Answer: C
Deep rationale: Irreversibility is marked by inability to reverse
mitochondrial dysfunction and profound membrane damage (plasma and
organellar membranes). While swelling, fatty change, and ER/ribosome
changes are reversible, catastrophic mitochondrial failure plus membrane
permeability loss commits the cell to death (necrosis/apoptosis), even if oxygen
is restored.
Key words: irreversible injury, mitochondrial permeability, membrane damage,
point of no return
8) Calcium in cell injury
Which downstream effect of increased cytosolic Ca²⁺ most directly amplifies
cellular injury?
, A. Activation of endonucleases, proteases, phospholipases, and ATPases
B. Inhibition of caspases
C. Stabilization of lysosomal membranes
D. Increased glycogen synthesis
Answer: A
Deep rationale: Increased intracellular Ca²⁺ activates multiple degradative
enzymes: phospholipases (membrane damage), proteases (cytoskeletal
damage), endonucleases (DNA fragmentation), and ATPases (worsen ATP
depletion). This creates a self-reinforcing injury cascade. Ca²⁺ does not inhibit
caspases, stabilize lysosomes, or promote glycogen synthesis as a primary
injury mechanism.
Key words: calcium influx, phospholipase, protease, endonuclease, membrane
damage
9) Reactive oxygen species (ROS)
A toxin causes excess free radical generation. Which cellular defense most
directly converts hydrogen peroxide (H₂O₂) into water?
A. Superoxide dismutase
B. Catalase
C. NADPH oxidase
D. Myeloperoxidase
Answer: B
Deep rationale: Catalase (peroxisomes) converts H₂O₂ → H₂O + O₂. Superoxide
dismutase converts superoxide to H₂O₂, which must then be cleared by catalase
or glutathione peroxidase. NADPH oxidase generates superoxide in phagocytes;
myeloperoxidase uses H₂O₂ to form hypochlorite.
Key words: ROS, hydrogen peroxide, catalase, antioxidant defense
10) Ischemia vs hypoxia
Compared with hypoxia due to decreased oxygen content (e.g., anemia),
ischemia generally causes more rapid and severe injury because it also
reduces:
A. Mitochondrial DNA replication
B. Delivery of glucose and removal of metabolic wastes
Chapter 1: Cell Adaptation, Injury, Death, and Aging
Chapter 2: Inflammation and Repair
Chapter 3: Immunopathology
Chapter 4: Neoplasia
Chapter 5: Developmental and Genetic Diseases
Chapter 6: Infectious and Parasitic Diseases
Chapter 7: The Amyloidoses
Chapter 8: Blood Vessels and Hemodynamic Disorders
Chapter 9: Heart
Chapter 10: The Respiratory System
Chapter 11: The Gastrointestinal Tract
Chapter 12: The Liver and Biliary System
Chapter 13: The Exocrine Pancreas
Chapter 14: The Kidney
Chapter 15: The Lower Urinary Tract and Male Reproductive System
Chapter 16: The Female Reproductive Tract
Chapter 17: The Breast
Chapter 18: Hematopathology
Chapter 19: Endocrine System, Diabetes, and Nutritional Diseases
Chapter 20: The Skin
Chapter 21: The Head and Neck
Chapter 22: Bones, Joints, and Soft Tissue
Chapter 23: Skeletal Muscle
Chapter 24: The Central Nervous System and Eye
Chapter 25: Traumatic and Environmental Injury
,Chapter 1: Cell Adaptation, Injury, Death, and
Aging — Test Bank (20 Advanced MCQs)
1) Cellular adaptation to increased workload
A 28-year-old athlete develops increased left ventricular wall thickness after
months of endurance training. Cardiomyocytes show enlarged cell size without
increased cell number. Which molecular change most directly drives this
adaptation?
A. Increased cyclin D expression causing G1→S transition
B. Upregulation of fetal gene program with increased protein synthesis
C. Activation of telomerase with chromosomal stabilization
D. Increased DNA replication with polyploidy
Answer: B
Deep rationale: Mature cardiomyocytes have minimal proliferative capacity, so
increased workload triggers hypertrophy, not hyperplasia. Hypertrophy is
mediated by mechanosensors and growth factor signaling (e.g., IGF-1), leading
to increased protein synthesis, sarcomere remodeling, and re-expression of a
fetal gene program (e.g., β-myosin heavy chain). Cyclin-driven cell cycle entry
is not the principal mechanism here, telomerase activation relates to replicative
aging, and polyploidy may occur in some tissues but is not the core driver of
physiologic cardiac hypertrophy.
Key words: hypertrophy, fetal gene program, cardiomyocyte, protein synthesis
2) Pathologic hypertrophy signaling
A 62-year-old with long-standing hypertension develops concentric left
ventricular hypertrophy. Which signaling pathway is most associated with
pathologic hypertrophy and eventual maladaptive remodeling?
A. PI3K–Akt (physiologic growth)
B. Gq-coupled receptor signaling leading to calcineurin–NFAT activation
C. p53-mediated apoptosis due to DNA damage
D. HIF-1α stabilization due to hypoxia
,Answer: B
Deep rationale: Pathologic hypertrophy commonly results from pressure
overload and neurohumoral stimulation (angiotensin II, endothelin,
catecholamines), which activates Gq-coupled receptors, increasing
intracellular Ca²⁺ and stimulating calcineurin–NFAT transcriptional
responses. This drives maladaptive gene expression, fibrosis, and risk of heart
failure. PI3K–Akt is classically linked to more physiologic hypertrophy. p53 and
HIF-1α can be involved in injury contexts but are not the main hypertrophic
program linked to pressure-overload remodeling.
Key words: pressure overload, calcineurin, NFAT, Gq, maladaptive remodeling
3) Hyperplasia vs hypertrophy
A patient with benign prostatic enlargement has increased organ size due to
increased number of glandular cells. Which statement best explains why this
process is possible in the prostate but not in adult cardiac muscle?
A. Prostate cells have more mitochondria than cardiomyocytes
B. Prostate has a cell population capable of entering the cell cycle;
cardiomyocytes are largely post-mitotic
C. Prostate cells rely on anaerobic metabolism; cardiomyocytes do not
D. Prostate cells do not undergo apoptosis; cardiomyocytes do
Answer: B
Deep rationale: Hyperplasia requires cells capable of proliferation
(stem/progenitor cells or differentiated cells that can re-enter the cycle). The
prostate retains cells responsive to hormonal growth signals (androgen-driven),
enabling increased cell number. Adult cardiomyocytes are terminally
differentiated with minimal regenerative capacity, so they adapt mainly by
hypertrophy. Metabolic and apoptosis differences do not explain the
fundamental capacity for hyperplasia.
Key words: hyperplasia, post-mitotic cells, prostate, regenerative capacity
4) Atrophy mechanism
A 72-year-old with prolonged immobilization after a hip fracture develops
marked quadriceps wasting. Which intracellular process most directly mediates
the reduction in cell size?
A. Increased glycolysis
B. Lysosomal storage of lipofuscin
,C. Ubiquitin–proteasome–mediated protein degradation
D. Increased telomerase activity
Answer: C
Deep rationale: Disuse atrophy is driven by decreased protein synthesis and
increased protein breakdown, especially via the ubiquitin–proteasome
pathway. Autophagy can also contribute, but proteasomal degradation is a key
mechanism for rapid loss of myofibrillar proteins. Lipofuscin is an aging
pigment, telomerase relates to replicative senescence, and glycolysis is not the
primary driver of atrophic protein loss.
Key words: disuse atrophy, ubiquitin-proteasome, protein degradation,
immobilization
5) Metaplasia and risk
A 48-year-old with long-standing gastroesophageal reflux develops intestinal-
type epithelium in the distal esophagus. Which best explains why this adaptive
change can increase cancer risk over time?
A. Metaplasia permanently prevents DNA damage
B. The replacement epithelium is more sensitive to acid injury
C. Persistent stress and inflammatory signaling increase proliferation, raising
mutation accumulation risk
D. Metaplasia is a form of apoptosis
Answer: C
Deep rationale: Metaplasia is a reversible adaptive substitution of one
differentiated cell type for another better suited to the stress environment.
However, chronic injury and inflammation can drive ongoing cell turnover
and proliferative signaling, increasing opportunities for genetic/epigenetic
alterations, progression to dysplasia, and carcinoma. Metaplasia does not
prevent DNA damage, and it is not apoptosis; the new epithelium is often more
resistant to the original stressor, not more sensitive.
Key words: metaplasia, Barrett esophagus, dysplasia, chronic inflammation,
carcinogenesis
6) Reversible injury hallmark
During transient myocardial ischemia, cardiomyocytes show swelling and
membrane blebs, but recover fully after reperfusion within minutes. Which
change most directly causes this reversible cell swelling?
,A. Increased intracellular calcium from ER rupture
B. ATP depletion leading to failure of Na⁺/K⁺-ATPase
C. Lysosomal membrane rupture with enzyme release
D. DNA fragmentation by endonucleases
Answer: B
Deep rationale: Early reversible injury is dominated by ATP depletion due to
impaired oxidative phosphorylation. ATP depletion causes failure of the Na⁺/K⁺-
ATPase, leading to Na⁺ and water influx → cell swelling (hydropic change),
plus membrane blebbing and ER dilation. Lysosomal rupture and DNA
fragmentation are associated with irreversible injury/cell death.
Key words: reversible injury, hydropic change, ATP depletion, Na/K pump,
ischemia
7) Transition to irreversible injury
A tissue experiences prolonged ischemia. Which event most strongly indicates
the injury has become irreversible?
A. Cellular swelling
B. Fatty change
C. Severe mitochondrial dysfunction with inability to restore ATP production
and membrane integrity
D. Ribosome detachment from rough ER
Answer: C
Deep rationale: Irreversibility is marked by inability to reverse
mitochondrial dysfunction and profound membrane damage (plasma and
organellar membranes). While swelling, fatty change, and ER/ribosome
changes are reversible, catastrophic mitochondrial failure plus membrane
permeability loss commits the cell to death (necrosis/apoptosis), even if oxygen
is restored.
Key words: irreversible injury, mitochondrial permeability, membrane damage,
point of no return
8) Calcium in cell injury
Which downstream effect of increased cytosolic Ca²⁺ most directly amplifies
cellular injury?
, A. Activation of endonucleases, proteases, phospholipases, and ATPases
B. Inhibition of caspases
C. Stabilization of lysosomal membranes
D. Increased glycogen synthesis
Answer: A
Deep rationale: Increased intracellular Ca²⁺ activates multiple degradative
enzymes: phospholipases (membrane damage), proteases (cytoskeletal
damage), endonucleases (DNA fragmentation), and ATPases (worsen ATP
depletion). This creates a self-reinforcing injury cascade. Ca²⁺ does not inhibit
caspases, stabilize lysosomes, or promote glycogen synthesis as a primary
injury mechanism.
Key words: calcium influx, phospholipase, protease, endonuclease, membrane
damage
9) Reactive oxygen species (ROS)
A toxin causes excess free radical generation. Which cellular defense most
directly converts hydrogen peroxide (H₂O₂) into water?
A. Superoxide dismutase
B. Catalase
C. NADPH oxidase
D. Myeloperoxidase
Answer: B
Deep rationale: Catalase (peroxisomes) converts H₂O₂ → H₂O + O₂. Superoxide
dismutase converts superoxide to H₂O₂, which must then be cleared by catalase
or glutathione peroxidase. NADPH oxidase generates superoxide in phagocytes;
myeloperoxidase uses H₂O₂ to form hypochlorite.
Key words: ROS, hydrogen peroxide, catalase, antioxidant defense
10) Ischemia vs hypoxia
Compared with hypoxia due to decreased oxygen content (e.g., anemia),
ischemia generally causes more rapid and severe injury because it also
reduces:
A. Mitochondrial DNA replication
B. Delivery of glucose and removal of metabolic wastes
