WGU D115
Advanced Pathophysiology (OA)
Questions and Answers| Latest Update| Pass Guaranteed
1. A weightlifter's cardiac muscle cells increase in size due to chronic pressure and
volume demands. Which cellular adaptation is occurring?
A. Hyperplasia
B. Hypertrophy
C. Atrophy
D. Metaplasia
Answer: B. Hypertrophy
Rationale: Hypertrophy is an increase in cell size (not number) in response to increased
functional demand, common in cardiac and skeletal muscle, which are composed of
permanent cells that cannot readily divide. Hyperplasia involves an increase in cell
number and occurs in tissues capable of mitosis. Atrophy is a decrease in cell size, and
metaplasia is replacement of one differentiated cell type with another.
2. Which finding is considered the point of no return, marking irreversible cellular
injury?
A. Cellular swelling
B. Fatty change
C. Severe mitochondrial vacuolization with calcium influx
D. Decreased protein synthesis
Answer: C. Severe mitochondrial vacuolization with calcium influx
Rationale: Irreversible injury is marked by severe mitochondrial damage and massive
calcium influx into the cell, which activates destructive enzymes (phospholipases,
proteases, ATPases) that degrade membranes and cellular structures. Cellular swelling
and fatty change are reversible findings seen early in cell injury before the point of no
return.
,3. Free radical-mediated cell injury primarily damages cells through which mechanism?
A. Direct DNA replication errors only
B. Lipid peroxidation of cell membranes
C. Enhanced ATP production
D. Increased antioxidant activity
Answer: B. Lipid peroxidation of cell membranes
Rationale: Free radicals are unstable molecules with unpaired electrons that steal
electrons from lipids in cell membranes, causing lipid peroxidation, which disrupts
membrane integrity and function. They also damage proteins and DNA, but membrane
lipid peroxidation is a hallmark mechanism of oxidative cell injury.
4. A nurse is differentiating apoptosis from necrosis. Which statement correctly
describes apoptosis?
A. It causes an inflammatory response in surrounding tissue
B. It is always pathologic and never a normal process
C. It is a programmed, energy-dependent process that does not trigger inflammation
D. It results in cell swelling and membrane rupture
Answer: C. It is a programmed, energy-dependent process that does not trigger
inflammation
Rationale: Apoptosis is a genetically programmed, ATP-dependent form of cell death in
which the cell shrinks, fragments into apoptotic bodies, and is phagocytosed without
spilling cellular contents, so it does not incite inflammation. Necrosis, in contrast,
involves cell swelling, membrane rupture, and release of intracellular contents that
trigger an inflammatory response.
5. During ischemia-reperfusion injury, tissue damage is worsened upon restoration of
blood flow primarily because of:
A. Decreased oxygen delivery to the tissue
B. Generation of reactive oxygen species when oxygen is reintroduced
C. Immediate return of normal ATP levels
D. Suppression of the inflammatory response
Answer: B. Generation of reactive oxygen species when oxygen is reintroduced
Rationale: When blood flow and oxygen are restored to previously ischemic tissue, the
sudden reintroduction of oxygen fuels the production of reactive oxygen species (free
radicals) by damaged mitochondria and infiltrating neutrophils, paradoxically worsening
cellular injury beyond what ischemia alone caused.
,6. Coagulative necrosis, characterized by preserved tissue architecture with cell death,
is most classically associated with:
A. Bacterial abscess formation
B. Myocardial infarction
C. Brain infarction
D. Caseous necrosis in tuberculosis
Answer: B. Myocardial infarction
Rationale: Coagulative necrosis occurs when protein denaturation predominates over
enzymatic digestion, preserving the basic tissue outline for days; it is the classic pattern
seen in infarction of solid organs such as the heart and kidney. Brain infarction instead
produces liquefactive necrosis due to high lipid content and enzymatic autolysis.
7. Liquefactive necrosis with formation of a soft, liquid center filled with dead cells is
most characteristic of injury to which tissue?
A. Myocardium
B. Kidney
C. Brain
D. Spleen
Answer: C. Brain
Rationale: Brain tissue is high in lipid content and lacks substantial supportive stroma, so
hypoxic injury leads to enzymatic digestion and liquefaction of dead tissue rather than
preservation of architecture, producing a fluid-filled cystic cavity. This differs from the
coagulative necrosis typical of the heart and kidney.
8. When a cell is deprived of oxygen, which sequence best reflects the early
biochemical events of hypoxic injury?
A. Increased ATP synthesis, decreased anaerobic glycolysis, cell shrinkage
B. Decreased ATP, failure of the sodium-potassium pump, cellular swelling
C. Immediate DNA fragmentation followed by ATP normalization
D. Increased protein synthesis and decreased calcium influx
Answer: B. Decreased ATP, failure of the sodium-potassium pump, cellular swelling
Rationale: Hypoxia halts oxidative phosphorylation, rapidly depleting ATP. Without ATP,
the sodium-potassium ATPase pump fails, sodium and water accumulate intracellularly
causing cellular/mitochondrial swelling, and anaerobic glycolysis increases, producing
lactic acid and lowering intracellular pH.
, 9. Which feature distinguishes chronic inflammation from acute inflammation?
A. Predominance of neutrophils
B. Presence of macrophages, lymphocytes, and fibrosis
C. Resolution within 48-72 hours
D. Formation of exudate only
Answer: B. Presence of macrophages, lymphocytes, and fibrosis
Rationale: Acute inflammation is characterized by neutrophil infiltration and vascular
changes lasting hours to days. Chronic inflammation persists for weeks to months and is
characterized by mononuclear cells (macrophages, lymphocytes, plasma cells), tissue
destruction, and concurrent attempts at repair including fibrosis and angiogenesis.
10. Mast cell degranulation releases histamine, which produces which local effect
during acute inflammation?
A. Vasoconstriction and decreased capillary permeability
B. Vasodilation and increased vascular permeability
C. Platelet aggregation and clot stabilization
D. Suppression of leukocyte migration
Answer: B. Vasodilation and increased vascular permeability
Rationale: Histamine released from mast cells and basophils causes arteriolar
vasodilation and increased permeability of postcapillary venules, allowing plasma
proteins and fluid to leak into tissue, producing the redness and swelling characteristic of
acute inflammation.
11. The complement fragments C3a and C5a are best described functionally as:
A. Opsonins that promote phagocytosis
B. Anaphylatoxins that trigger mast cell degranulation and chemotaxis
C. Antibodies that neutralize antigens
D. Membrane attack complex components that lyse cells
Answer: B. Anaphylatoxins that trigger mast cell degranulation and chemotaxis
Rationale: C3a and C5a are anaphylatoxins that stimulate mast cell and basophil
histamine release, increase vascular permeability, and act as chemotactic factors
(especially C5a) that recruit neutrophils to the site of injury. C3b, not C3a, functions as
the major opsonin, and C5b-9 forms the membrane attack complex.
Advanced Pathophysiology (OA)
Questions and Answers| Latest Update| Pass Guaranteed
1. A weightlifter's cardiac muscle cells increase in size due to chronic pressure and
volume demands. Which cellular adaptation is occurring?
A. Hyperplasia
B. Hypertrophy
C. Atrophy
D. Metaplasia
Answer: B. Hypertrophy
Rationale: Hypertrophy is an increase in cell size (not number) in response to increased
functional demand, common in cardiac and skeletal muscle, which are composed of
permanent cells that cannot readily divide. Hyperplasia involves an increase in cell
number and occurs in tissues capable of mitosis. Atrophy is a decrease in cell size, and
metaplasia is replacement of one differentiated cell type with another.
2. Which finding is considered the point of no return, marking irreversible cellular
injury?
A. Cellular swelling
B. Fatty change
C. Severe mitochondrial vacuolization with calcium influx
D. Decreased protein synthesis
Answer: C. Severe mitochondrial vacuolization with calcium influx
Rationale: Irreversible injury is marked by severe mitochondrial damage and massive
calcium influx into the cell, which activates destructive enzymes (phospholipases,
proteases, ATPases) that degrade membranes and cellular structures. Cellular swelling
and fatty change are reversible findings seen early in cell injury before the point of no
return.
,3. Free radical-mediated cell injury primarily damages cells through which mechanism?
A. Direct DNA replication errors only
B. Lipid peroxidation of cell membranes
C. Enhanced ATP production
D. Increased antioxidant activity
Answer: B. Lipid peroxidation of cell membranes
Rationale: Free radicals are unstable molecules with unpaired electrons that steal
electrons from lipids in cell membranes, causing lipid peroxidation, which disrupts
membrane integrity and function. They also damage proteins and DNA, but membrane
lipid peroxidation is a hallmark mechanism of oxidative cell injury.
4. A nurse is differentiating apoptosis from necrosis. Which statement correctly
describes apoptosis?
A. It causes an inflammatory response in surrounding tissue
B. It is always pathologic and never a normal process
C. It is a programmed, energy-dependent process that does not trigger inflammation
D. It results in cell swelling and membrane rupture
Answer: C. It is a programmed, energy-dependent process that does not trigger
inflammation
Rationale: Apoptosis is a genetically programmed, ATP-dependent form of cell death in
which the cell shrinks, fragments into apoptotic bodies, and is phagocytosed without
spilling cellular contents, so it does not incite inflammation. Necrosis, in contrast,
involves cell swelling, membrane rupture, and release of intracellular contents that
trigger an inflammatory response.
5. During ischemia-reperfusion injury, tissue damage is worsened upon restoration of
blood flow primarily because of:
A. Decreased oxygen delivery to the tissue
B. Generation of reactive oxygen species when oxygen is reintroduced
C. Immediate return of normal ATP levels
D. Suppression of the inflammatory response
Answer: B. Generation of reactive oxygen species when oxygen is reintroduced
Rationale: When blood flow and oxygen are restored to previously ischemic tissue, the
sudden reintroduction of oxygen fuels the production of reactive oxygen species (free
radicals) by damaged mitochondria and infiltrating neutrophils, paradoxically worsening
cellular injury beyond what ischemia alone caused.
,6. Coagulative necrosis, characterized by preserved tissue architecture with cell death,
is most classically associated with:
A. Bacterial abscess formation
B. Myocardial infarction
C. Brain infarction
D. Caseous necrosis in tuberculosis
Answer: B. Myocardial infarction
Rationale: Coagulative necrosis occurs when protein denaturation predominates over
enzymatic digestion, preserving the basic tissue outline for days; it is the classic pattern
seen in infarction of solid organs such as the heart and kidney. Brain infarction instead
produces liquefactive necrosis due to high lipid content and enzymatic autolysis.
7. Liquefactive necrosis with formation of a soft, liquid center filled with dead cells is
most characteristic of injury to which tissue?
A. Myocardium
B. Kidney
C. Brain
D. Spleen
Answer: C. Brain
Rationale: Brain tissue is high in lipid content and lacks substantial supportive stroma, so
hypoxic injury leads to enzymatic digestion and liquefaction of dead tissue rather than
preservation of architecture, producing a fluid-filled cystic cavity. This differs from the
coagulative necrosis typical of the heart and kidney.
8. When a cell is deprived of oxygen, which sequence best reflects the early
biochemical events of hypoxic injury?
A. Increased ATP synthesis, decreased anaerobic glycolysis, cell shrinkage
B. Decreased ATP, failure of the sodium-potassium pump, cellular swelling
C. Immediate DNA fragmentation followed by ATP normalization
D. Increased protein synthesis and decreased calcium influx
Answer: B. Decreased ATP, failure of the sodium-potassium pump, cellular swelling
Rationale: Hypoxia halts oxidative phosphorylation, rapidly depleting ATP. Without ATP,
the sodium-potassium ATPase pump fails, sodium and water accumulate intracellularly
causing cellular/mitochondrial swelling, and anaerobic glycolysis increases, producing
lactic acid and lowering intracellular pH.
, 9. Which feature distinguishes chronic inflammation from acute inflammation?
A. Predominance of neutrophils
B. Presence of macrophages, lymphocytes, and fibrosis
C. Resolution within 48-72 hours
D. Formation of exudate only
Answer: B. Presence of macrophages, lymphocytes, and fibrosis
Rationale: Acute inflammation is characterized by neutrophil infiltration and vascular
changes lasting hours to days. Chronic inflammation persists for weeks to months and is
characterized by mononuclear cells (macrophages, lymphocytes, plasma cells), tissue
destruction, and concurrent attempts at repair including fibrosis and angiogenesis.
10. Mast cell degranulation releases histamine, which produces which local effect
during acute inflammation?
A. Vasoconstriction and decreased capillary permeability
B. Vasodilation and increased vascular permeability
C. Platelet aggregation and clot stabilization
D. Suppression of leukocyte migration
Answer: B. Vasodilation and increased vascular permeability
Rationale: Histamine released from mast cells and basophils causes arteriolar
vasodilation and increased permeability of postcapillary venules, allowing plasma
proteins and fluid to leak into tissue, producing the redness and swelling characteristic of
acute inflammation.
11. The complement fragments C3a and C5a are best described functionally as:
A. Opsonins that promote phagocytosis
B. Anaphylatoxins that trigger mast cell degranulation and chemotaxis
C. Antibodies that neutralize antigens
D. Membrane attack complex components that lyse cells
Answer: B. Anaphylatoxins that trigger mast cell degranulation and chemotaxis
Rationale: C3a and C5a are anaphylatoxins that stimulate mast cell and basophil
histamine release, increase vascular permeability, and act as chemotactic factors
(especially C5a) that recruit neutrophils to the site of injury. C3b, not C3a, functions as
the major opsonin, and C5b-9 forms the membrane attack complex.
