WGU D236 Pathophysiology Final Exam | Complete
Practice QUESTIONs, Verified Answers & Detailed
Rationales (2026/2027)
QUESTION 1
Which type of cellular adaptation involves the replacement of one
mature cell type by another, often as a result of chronic irritation or
inflammation?
• A. Hypertrophy
• B. Metaplasia
• C. Dysplasia
• D. Atrophy
Correct Answer: B. Metaplasia
Detailed Rationale: Metaplasia is the reversible replacement of one
mature cell type by another, sometimes less differentiated, cell type,
typically in response to chronic irritation or injury (e.g., ciliated
columnar cells changing to stratified squamous cells in the airways of
chronic smokers).
QUESTION 2
Which electrolyte imbalance is most commonly associated with cellular
swelling (cellular edema) during acute ischemic injury?
• A. Intracellular accumulation of potassium
• B. Intracellular accumulation of sodium and water
, • C. Extracellular loss of calcium
• D. Extracellular accumulation of magnesium
Correct Answer: B. Intracellular accumulation of sodium and water
Detailed Rationale: Ischemia impairs ATP production, which causes
failure of the 𝑁𝑎+ /𝐾 + ATPase pump. Sodium accumulates
intracellularly, drawing water into the cell via osmosis and leading to
acute cellular swelling.
QUESTION 3
What is the recurrence risk for an autosomal recessive genetic disorder
when both parents are carriers (heterozygous)?
• A. 0%
• B. 25%
• C. 50%
• D. 100%
Correct Answer: B. 25%
Detailed Rationale: In an autosomal recessive inheritance pattern, two
carrier parents (𝐴𝑎 × 𝐴𝑎) have a 25% chance of having an affected
child (𝑎𝑎), a 50% chance of having a carrier child (𝐴𝑎), and a 25%
chance of having a normal non-carrier child (𝐴𝐴).
QUESTION 4
Which type of hypersensitivity reaction is mediated by IgE antibodies
and involves mast cell degranulation?
• A. Type I
, • B. Type II
• C. Type III
• D. Type IV
Correct Answer: A. Type I
Detailed Rationale: Type I hypersensitivity is an immediate allergic
reaction mediated by IgE antibodies binding to mast cells and basophils,
causing the release of histamine and other inflammatory mediators
upon subsequent allergen exposure.
QUESTION 5
A patient presents with arterial blood gas results showing: pH = 7.30,
𝑃𝑎𝐶𝑂2 = 55 mmHg, 𝐻𝐶𝑂3− = 24 mEq/L. What is the primary acid-base
disturbance?
• A. Metabolic acidosis
• B. Metabolic alkalosis
• C. Respiratory acidosis
• D. Respiratory alkalosis
Correct Answer: C. Respiratory acidosis
Detailed Rationale: A low pH (< 7.35) indicates acidemia. A high
𝑃𝑎𝐶𝑂2 (> 45 mmHg) reflects hypoventilation leading to carbon dioxide
retention. Carbon dioxide combines with water to form carbonic acid,
which dissociates into hydrogen ions, causing respiratory acidosis.
QUESTION 6
, What is the initial event in the development of an atherosclerotic
plaque?
• A. Smooth muscle cell proliferation in the tunica media
• B. Endothelial injury and dysfunction
• C. Calcium deposition in the arterial wall
• D. Rupture of an unstable fibrous cap
Correct Answer: B. Endothelial injury and dysfunction
Detailed Rationale: Atherosclerosis begins with endothelial injury
caused by factors like hypertension, smoking, or hyperlipidemia, which
increases vascular permeability and attracts inflammatory cells and
lipids into the vessel wall.
QUESTION 7
Which clinical manifestation is characteristic of left-sided heart failure
rather than right-sided heart failure?
• A. Jugular venous distension
• B. Peripheral pitting edema
• C. Pulmonary congestion and dyspnea
• D. Hepatomegaly and splenomegaly
Correct Answer: C. Pulmonary congestion and dyspnea
Detailed Rationale: Left-sided heart failure causes blood to back up into
the pulmonary circulation, resulting in pulmonary congestion, dyspnea,
orthopnea, and crackles. Right-sided failure causes systemic congestion
(jugular venous distension, peripheral edema, ascites).
Practice QUESTIONs, Verified Answers & Detailed
Rationales (2026/2027)
QUESTION 1
Which type of cellular adaptation involves the replacement of one
mature cell type by another, often as a result of chronic irritation or
inflammation?
• A. Hypertrophy
• B. Metaplasia
• C. Dysplasia
• D. Atrophy
Correct Answer: B. Metaplasia
Detailed Rationale: Metaplasia is the reversible replacement of one
mature cell type by another, sometimes less differentiated, cell type,
typically in response to chronic irritation or injury (e.g., ciliated
columnar cells changing to stratified squamous cells in the airways of
chronic smokers).
QUESTION 2
Which electrolyte imbalance is most commonly associated with cellular
swelling (cellular edema) during acute ischemic injury?
• A. Intracellular accumulation of potassium
• B. Intracellular accumulation of sodium and water
, • C. Extracellular loss of calcium
• D. Extracellular accumulation of magnesium
Correct Answer: B. Intracellular accumulation of sodium and water
Detailed Rationale: Ischemia impairs ATP production, which causes
failure of the 𝑁𝑎+ /𝐾 + ATPase pump. Sodium accumulates
intracellularly, drawing water into the cell via osmosis and leading to
acute cellular swelling.
QUESTION 3
What is the recurrence risk for an autosomal recessive genetic disorder
when both parents are carriers (heterozygous)?
• A. 0%
• B. 25%
• C. 50%
• D. 100%
Correct Answer: B. 25%
Detailed Rationale: In an autosomal recessive inheritance pattern, two
carrier parents (𝐴𝑎 × 𝐴𝑎) have a 25% chance of having an affected
child (𝑎𝑎), a 50% chance of having a carrier child (𝐴𝑎), and a 25%
chance of having a normal non-carrier child (𝐴𝐴).
QUESTION 4
Which type of hypersensitivity reaction is mediated by IgE antibodies
and involves mast cell degranulation?
• A. Type I
, • B. Type II
• C. Type III
• D. Type IV
Correct Answer: A. Type I
Detailed Rationale: Type I hypersensitivity is an immediate allergic
reaction mediated by IgE antibodies binding to mast cells and basophils,
causing the release of histamine and other inflammatory mediators
upon subsequent allergen exposure.
QUESTION 5
A patient presents with arterial blood gas results showing: pH = 7.30,
𝑃𝑎𝐶𝑂2 = 55 mmHg, 𝐻𝐶𝑂3− = 24 mEq/L. What is the primary acid-base
disturbance?
• A. Metabolic acidosis
• B. Metabolic alkalosis
• C. Respiratory acidosis
• D. Respiratory alkalosis
Correct Answer: C. Respiratory acidosis
Detailed Rationale: A low pH (< 7.35) indicates acidemia. A high
𝑃𝑎𝐶𝑂2 (> 45 mmHg) reflects hypoventilation leading to carbon dioxide
retention. Carbon dioxide combines with water to form carbonic acid,
which dissociates into hydrogen ions, causing respiratory acidosis.
QUESTION 6
, What is the initial event in the development of an atherosclerotic
plaque?
• A. Smooth muscle cell proliferation in the tunica media
• B. Endothelial injury and dysfunction
• C. Calcium deposition in the arterial wall
• D. Rupture of an unstable fibrous cap
Correct Answer: B. Endothelial injury and dysfunction
Detailed Rationale: Atherosclerosis begins with endothelial injury
caused by factors like hypertension, smoking, or hyperlipidemia, which
increases vascular permeability and attracts inflammatory cells and
lipids into the vessel wall.
QUESTION 7
Which clinical manifestation is characteristic of left-sided heart failure
rather than right-sided heart failure?
• A. Jugular venous distension
• B. Peripheral pitting edema
• C. Pulmonary congestion and dyspnea
• D. Hepatomegaly and splenomegaly
Correct Answer: C. Pulmonary congestion and dyspnea
Detailed Rationale: Left-sided heart failure causes blood to back up into
the pulmonary circulation, resulting in pulmonary congestion, dyspnea,
orthopnea, and crackles. Right-sided failure causes systemic congestion
(jugular venous distension, peripheral edema, ascites).
