D. Decreased renin secretion
MIDTERM 2 EXAM QUESTIONS AND CORRECT
Answer: B
ANSWERS WITH RATIONALES GRADED A+ Rationale: Increased preload stretches myocardial fibers → stronger contraction to
LATEST maintain CO.
1. Which is the primary pathophysiologic mechanism in acute myocardial 4. Which lab marker is most specific for liver synthetic function?
infarction? A. ALT
A. Coronary vasospasm B. AST
B. Plaque rupture → thrombus → ischemia C. Albumin
C. Viral infection D. Bilirubin
D. Aortic stenosis Answer: C
Answer: B Rationale: Low albumin indicates impaired hepatic protein synthesis.
Rationale: Most MIs result from atherosclerotic plaque rupture → thrombosis →
occlusion → myocardial ischemia.
5. Which type of shock is characterized by low systemic vascular resistance
and warm extremities?
2. Which arrhythmia is most commonly associated with acute MI? A. Hypovolemic
A. Atrial fibrillation B. Cardiogenic
B. Ventricular tachycardia/fibrillation C. Obstructive
C. Sinus bradycardia D. Distributive (septic)
D. Junctional rhythm Answer: D
Answer: B Rationale: Vasodilation → hypotension with warm peripheries.
Rationale: Ischemia causes electrical instability → life-threatening ventricular
arrhythmias.
6. Which electrolyte imbalance is most commonly associated with chronic
kidney disease?
3. In left-sided heart failure, which compensatory mechanism is initially A. Hypokalemia
activated? B. Hyperkalemia
A. Decreased sympathetic tone C. Hypocalcemia only
B. Frank-Starling mechanism (increased preload) D. Hypernatremia
,Answer: B C. Increased lymph drainage
Rationale: Reduced renal excretion → K⁺ retention. D. Hypernatremia
Answer: B
Rationale: Proteinuria → hypoalbuminemia → fluid shifts into interstitial spaces.
7. Which type of necrosis is typical of ischemic heart tissue?
A. Coagulative
B. Liquefactive
11. Which lab value is most sensitive for early kidney injury?
C. Caseous
A. BUN
D. Fat
B. Creatinine
Answer: A C. Urine sodium
Rationale: Ischemia preserves tissue architecture initially → coagulative necrosis. D. LDH
Answer: B
Rationale: Creatinine rises early with decreased GFR.
8. Which acid-base disturbance occurs in COPD with CO₂ retention?
A. Metabolic acidosis
B. Chronic respiratory acidosis (compensated by ↑ HCO₃⁻)
12. Which electrolyte abnormality is associated with Addison’s disease?
C. Metabolic alkalosis
A. Hypernatremia, hypokalemia
D. Respiratory alkalosis
B. Hypokalemia only
Answer: B C. Hyponatremia, hyperkalemia
Rationale: Chronic CO₂ retention → renal compensation → increased HCO₃⁻. D. Hypercalcemia
Answer: C
Rationale: Aldosterone deficiency → Na⁺ loss, K⁺ retention.
9. Which lab marker rises earliest after myocardial injury?
A. CK-MB
B. Troponin
13. Which pathophysiologic mechanism underlies DKA?
C. Myoglobin
A. Excess insulin → hypoglycemia
D. LDH
B. Insulin deficiency → hyperglycemia → lipolysis → ketone production →
Answer: C metabolic acidosis
Rationale: Myoglobin rises 1–3 hours post-injury; troponins are more specific. C. Chronic hyperglycemia → protein catabolism
D. Increased glucose uptake
Answer: B
10. Which mechanism causes edema in nephrotic syndrome?
Rationale: Insulin deficiency prevents glucose utilization → fat breakdown →
A. Increased hydrostatic pressure
ketone accumulation.
B. Decreased oncotic pressure (protein loss)
, C. Hypermagnesemia
D. Hypocalcemia
14. Which acid-base disorder results from prolonged diarrhea?
A. Metabolic alkalosis Answer: D
B. Metabolic acidosis (loss of HCO₃⁻) Rationale: Low Ca²⁺ → increased neuromuscular excitability → tetany.
C. Respiratory acidosis
D. Respiratory alkalosis
18. Which hormone excess causes Cushing’s syndrome?
Answer: B
A. Cortisol
Rationale: Loss of bicarbonate in stool → decreased pH → acidosis.
B. Aldosterone
C. T3/T4
D. Cortisol
15. Which compensatory mechanism occurs in chronic hypoxia?
A. Decreased RBC production Answer: D
B. Increased erythropoietin → polycythemia Rationale: Cortisol excess → hyperglycemia, central obesity, muscle wasting.
C. Hypercapnia
D. Decreased cardiac output
19. Which electrolyte disturbance occurs in primary hyperaldosteronism?
Answer: B
A. Hyperkalemia
Rationale: Hypoxia stimulates kidneys → erythropoietin → RBC production.
B. Hypokalemia, hypernatremia
C. Hyponatremia
D. Hypercalcemia
16. Which lab finding indicates hemolytic anemia?
A. Decreased LDH Answer: B
B. Low reticulocytes Rationale: Aldosterone → Na⁺ retention, K⁺ excretion.
C. Elevated LDH, indirect bilirubin, reticulocyte count
D. Low uric acid
20. Which immune mechanism is involved in SLE?
Answer: C
A. IgE-mediated
Rationale: RBC destruction → ↑ LDH & indirect bilirubin; marrow compensates
B. Cytotoxic T-cell
→ ↑ reticulocytes.
C. Type III hypersensitivity (immune complexes)
D. Complement overactivation without antibodies
17. Which electrolyte imbalance can cause tetany? Answer: C
A. Hyperkalemia Rationale: Autoantibodies form complexes → tissue deposition → inflammation.
B. Hypokalemia