WGU D115 Advanced Pathophysiology OA-Style Practice 2026/2027
Exam verified with correct answers
1. A patient develops tissue hypoxia because of severe blood loss. Which cellular change
occurs first as oxygen delivery decreases?
A. Increased oxidative phosphorylation
B. Increased ATP production
C. Decreased aerobic metabolism
D. Increased protein synthesis
Answer: C. Decreased aerobic metabolism
Rationale: Reduced oxygen availability limits oxidative phosphorylation in mitochondria,
causing decreased ATP production and a shift toward anaerobic metabolism.
2. A patient experiences prolonged ischemia to cardiac tissue. Which cellular process
contributes to irreversible cell injury?
A. Mild cellular swelling
B. Reversible fatty change
C. Mitochondrial dysfunction with severe ATP depletion
D. Temporary reduction in protein synthesis
Answer: C. Mitochondrial dysfunction with severe ATP depletion
Rationale: Severe mitochondrial damage and profound ATP depletion impair membrane
integrity and essential cellular processes, contributing to irreversible injury.
3. A patient has an elevated serum C-reactive protein (CRP). What does this finding most
directly indicate?
A. Chronic hypoxia
B. Systemic inflammatory activity
C. Decreased immune activity
D. Impaired erythropoiesis
Answer: B. Systemic inflammatory activity
Rationale: CRP is an acute-phase protein produced primarily by the liver in response to
inflammatory cytokines and is commonly used as a marker of inflammation.
4. Which mediator is primarily responsible for causing vasodilation and increased vascular
permeability during acute inflammation?
,A. Histamine
B. Insulin
C. Erythropoietin
D. Albumin
Answer: A. Histamine
Rationale: Histamine released from mast cells promotes vasodilation and increases vascular
permeability, contributing to redness, warmth, and edema during acute inflammation.
5. A patient develops an allergic reaction immediately after exposure to an antigen. Which
immunoglobulin is primarily responsible?
A. IgA
B. IgG
C. IgM
D. IgE
Answer: D. IgE
Rationale: IgE mediates type I hypersensitivity reactions. It binds to mast cells and basophils,
leading to mediator release after allergen exposure.
6. A patient with rheumatoid arthritis has chronic joint inflammation caused by an abnormal
immune response. Which mechanism best explains this disease?
A. Autoimmunity against self-antigens
B. Complete absence of antibodies
C. Failure of innate immunity only
D. Excessive erythrocyte production
Answer: A. Autoimmunity against self-antigens
Rationale: Rheumatoid arthritis is an autoimmune disorder in which the immune system attacks
components of the synovial joints, producing chronic inflammation and tissue destruction.
7. A patient with left-sided heart failure develops dyspnea and pulmonary crackles. What is
the primary pathophysiologic mechanism?
A. Decreased pulmonary blood flow
B. Increased pulmonary venous pressure
C. Decreased systemic venous pressure
D. Increased renal filtration
Answer: B. Increased pulmonary venous pressure
,Rationale: Left ventricular dysfunction causes blood to back up into the pulmonary circulation,
increasing pulmonary capillary pressure and promoting pulmonary edema.
8. A patient with chronic hypertension develops left ventricular hypertrophy. Why does this
occur?
A. The heart must overcome increased systemic vascular resistance
B. Venous return completely stops
C. Pulmonary resistance decreases
D. Coronary blood flow becomes excessive
Answer: A. The heart must overcome increased systemic vascular resistance
Rationale: Chronic hypertension increases afterload. The left ventricle compensates by
increasing muscle mass to generate greater pressure against the elevated systemic resistance.
9. A patient with chronic obstructive pulmonary disease develops carbon dioxide retention.
Which acid-base disturbance is most likely?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Metabolic acidosis
Answer: C. Respiratory acidosis
Rationale: Hypoventilation and impaired CO₂ elimination cause carbon dioxide retention,
increasing carbonic acid and producing respiratory acidosis.
10. A patient with chronic kidney disease develops anemia. Which mechanism best explains
this finding?
A. Increased iron absorption
B. Decreased erythropoietin production
C. Increased platelet destruction
D. Increased red blood cell production
Answer: B. Decreased erythropoietin production
Rationale: Damaged kidneys produce less erythropoietin, a hormone that stimulates red blood
cell production in the bone marrow, resulting in anemia.
11. A patient with severe sepsis develops hypotension and impaired tissue perfusion. Which
cellular consequence is most likely?
, A. Increased ATP production
B. Increased aerobic metabolism
C. Cellular hypoxia with increased anaerobic metabolism
D. Increased mitochondrial efficiency
Answer: C. Cellular hypoxia with increased anaerobic metabolism
Rationale: Inadequate tissue perfusion decreases oxygen delivery. Cells compensate by
increasing anaerobic metabolism, which produces less ATP and increases lactic acid.
12. A patient develops metabolic acidosis after prolonged shock. Which laboratory finding
would the nurse expect?
A. Decreased lactate
B. Increased serum lactate
C. Increased bicarbonate
D. Increased blood pH
Answer: B. Increased serum lactate
Rationale: Poor tissue perfusion causes cells to rely on anaerobic metabolism, producing excess
lactic acid and increasing serum lactate.
13. A patient has hyperkalemia caused by acute kidney injury. Which cardiac manifestation
is most concerning?
A. Peaked T waves
B. Shortened PR interval only
C. Increased P-wave amplitude
D. Sinus tachycardia without ECG changes
Answer: A. Peaked T waves
Rationale: Hyperkalemia can cause characteristic ECG changes, including tall peaked T waves,
followed by progressive conduction abnormalities as potassium levels increase.
14. A patient with chronic kidney disease develops metabolic acidosis. Which mechanism
contributes most directly?
A. Excessive bicarbonate production
B. Inability to adequately excrete hydrogen ions
C. Increased pulmonary ventilation
D. Increased intestinal absorption of bicarbonate
Answer: B. Inability to adequately excrete hydrogen ions
Exam verified with correct answers
1. A patient develops tissue hypoxia because of severe blood loss. Which cellular change
occurs first as oxygen delivery decreases?
A. Increased oxidative phosphorylation
B. Increased ATP production
C. Decreased aerobic metabolism
D. Increased protein synthesis
Answer: C. Decreased aerobic metabolism
Rationale: Reduced oxygen availability limits oxidative phosphorylation in mitochondria,
causing decreased ATP production and a shift toward anaerobic metabolism.
2. A patient experiences prolonged ischemia to cardiac tissue. Which cellular process
contributes to irreversible cell injury?
A. Mild cellular swelling
B. Reversible fatty change
C. Mitochondrial dysfunction with severe ATP depletion
D. Temporary reduction in protein synthesis
Answer: C. Mitochondrial dysfunction with severe ATP depletion
Rationale: Severe mitochondrial damage and profound ATP depletion impair membrane
integrity and essential cellular processes, contributing to irreversible injury.
3. A patient has an elevated serum C-reactive protein (CRP). What does this finding most
directly indicate?
A. Chronic hypoxia
B. Systemic inflammatory activity
C. Decreased immune activity
D. Impaired erythropoiesis
Answer: B. Systemic inflammatory activity
Rationale: CRP is an acute-phase protein produced primarily by the liver in response to
inflammatory cytokines and is commonly used as a marker of inflammation.
4. Which mediator is primarily responsible for causing vasodilation and increased vascular
permeability during acute inflammation?
,A. Histamine
B. Insulin
C. Erythropoietin
D. Albumin
Answer: A. Histamine
Rationale: Histamine released from mast cells promotes vasodilation and increases vascular
permeability, contributing to redness, warmth, and edema during acute inflammation.
5. A patient develops an allergic reaction immediately after exposure to an antigen. Which
immunoglobulin is primarily responsible?
A. IgA
B. IgG
C. IgM
D. IgE
Answer: D. IgE
Rationale: IgE mediates type I hypersensitivity reactions. It binds to mast cells and basophils,
leading to mediator release after allergen exposure.
6. A patient with rheumatoid arthritis has chronic joint inflammation caused by an abnormal
immune response. Which mechanism best explains this disease?
A. Autoimmunity against self-antigens
B. Complete absence of antibodies
C. Failure of innate immunity only
D. Excessive erythrocyte production
Answer: A. Autoimmunity against self-antigens
Rationale: Rheumatoid arthritis is an autoimmune disorder in which the immune system attacks
components of the synovial joints, producing chronic inflammation and tissue destruction.
7. A patient with left-sided heart failure develops dyspnea and pulmonary crackles. What is
the primary pathophysiologic mechanism?
A. Decreased pulmonary blood flow
B. Increased pulmonary venous pressure
C. Decreased systemic venous pressure
D. Increased renal filtration
Answer: B. Increased pulmonary venous pressure
,Rationale: Left ventricular dysfunction causes blood to back up into the pulmonary circulation,
increasing pulmonary capillary pressure and promoting pulmonary edema.
8. A patient with chronic hypertension develops left ventricular hypertrophy. Why does this
occur?
A. The heart must overcome increased systemic vascular resistance
B. Venous return completely stops
C. Pulmonary resistance decreases
D. Coronary blood flow becomes excessive
Answer: A. The heart must overcome increased systemic vascular resistance
Rationale: Chronic hypertension increases afterload. The left ventricle compensates by
increasing muscle mass to generate greater pressure against the elevated systemic resistance.
9. A patient with chronic obstructive pulmonary disease develops carbon dioxide retention.
Which acid-base disturbance is most likely?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Metabolic acidosis
Answer: C. Respiratory acidosis
Rationale: Hypoventilation and impaired CO₂ elimination cause carbon dioxide retention,
increasing carbonic acid and producing respiratory acidosis.
10. A patient with chronic kidney disease develops anemia. Which mechanism best explains
this finding?
A. Increased iron absorption
B. Decreased erythropoietin production
C. Increased platelet destruction
D. Increased red blood cell production
Answer: B. Decreased erythropoietin production
Rationale: Damaged kidneys produce less erythropoietin, a hormone that stimulates red blood
cell production in the bone marrow, resulting in anemia.
11. A patient with severe sepsis develops hypotension and impaired tissue perfusion. Which
cellular consequence is most likely?
, A. Increased ATP production
B. Increased aerobic metabolism
C. Cellular hypoxia with increased anaerobic metabolism
D. Increased mitochondrial efficiency
Answer: C. Cellular hypoxia with increased anaerobic metabolism
Rationale: Inadequate tissue perfusion decreases oxygen delivery. Cells compensate by
increasing anaerobic metabolism, which produces less ATP and increases lactic acid.
12. A patient develops metabolic acidosis after prolonged shock. Which laboratory finding
would the nurse expect?
A. Decreased lactate
B. Increased serum lactate
C. Increased bicarbonate
D. Increased blood pH
Answer: B. Increased serum lactate
Rationale: Poor tissue perfusion causes cells to rely on anaerobic metabolism, producing excess
lactic acid and increasing serum lactate.
13. A patient has hyperkalemia caused by acute kidney injury. Which cardiac manifestation
is most concerning?
A. Peaked T waves
B. Shortened PR interval only
C. Increased P-wave amplitude
D. Sinus tachycardia without ECG changes
Answer: A. Peaked T waves
Rationale: Hyperkalemia can cause characteristic ECG changes, including tall peaked T waves,
followed by progressive conduction abnormalities as potassium levels increase.
14. A patient with chronic kidney disease develops metabolic acidosis. Which mechanism
contributes most directly?
A. Excessive bicarbonate production
B. Inability to adequately excrete hydrogen ions
C. Increased pulmonary ventilation
D. Increased intestinal absorption of bicarbonate
Answer: B. Inability to adequately excrete hydrogen ions
