Part 8: Disorders of Circulatory System & Miscellaneous (25 MCQs)

Part 8: Disorders of Circulatory System & Miscellaneous (25 MCQs)

Q1. Hypertension refers to:

A. Low blood pressure
B. Normal blood pressure
C. High blood pressure (>140/90 mmHg)
D. Irregular heartbeat

Answer: C

Explanation:

• A. Incorrect: Low BP = hypotension.
• B. Incorrect: Normal = 120/80 mmHg.
• C. Correct: Hypertension = persistent BP ≥140/90.
• D. Incorrect: Irregular rhythm = arrhythmia.

Q2. Which disorder is characterized by narrowing of coronary arteries due to fatty deposits?

A. Myocardial infarction
B. Atherosclerosis
C. Angina pectoris
D. Thrombosis

Answer: B

Explanation:

• A. Incorrect: Infarction = complete blockage.
• B. Correct: Atherosclerosis = plaque buildup.
• C. Incorrect: Angina = temporary chest pain due to poor supply.
• D. Incorrect: Thrombosis = clot formation.

Q3. “Silent killer” is a term often used for:

A. Diabetes
B. Hypertension
C. Anemia
D. Leukemia

Answer: B

Explanation:

• A. Incorrect: Diabetes causes long-term damage but not called silent killer in circulation context.
• B. Correct: Hypertension is symptomless but dangerous.
• C. Incorrect: Anemia is not silent.
• D. Incorrect: Leukemia is not asymptomatic early.

Q4. Which condition is caused by insufficient blood supply to the heart muscle?

A. Angina pectoris
B. Stroke
C. Hypertension
D. Varicose veins

Answer: A

Explanation:

• A. Correct: Angina = chest pain due to low oxygen supply to heart.
• B. Incorrect: Stroke affects brain.
• C. Incorrect: Hypertension is high BP.
• D. Incorrect: Varicose veins = vein valve defect.

Q5. Myocardial infarction (MI) refers to:

A. Enlargement of atria
B. Permanent death of cardiac muscle due to blocked blood supply
C. Increased blood clotting
D. Swelling of arteries

Answer: B

Explanation:

• A. Incorrect: Not atrial enlargement.
• B. Correct: MI = heart attack = necrosis due to blocked coronary artery.
• C. Incorrect: Not definition.
• D. Incorrect: Not swelling.

Q6. Heart failure differs from heart attack in that:

A. Heart failure = sudden blockage
B. Heart failure = pumping inefficiency, not sudden muscle death
C. Both are same
D. Heart failure = always fatal immediately

Answer: B

Explanation:

• A. Incorrect: Blockage = heart attack.
• B. Correct: Heart failure = weak pumping ability.
• C. Incorrect: They are distinct.
• D. Incorrect: Not always immediately fatal.

Q7. Which condition is caused by weakened venous valves leading to pooling of blood?

A. Thrombosis
B. Varicose veins
C. Stroke
D. Hypertension

Answer: B

Explanation:

• A. Incorrect: Thrombosis = clot formation.
• B. Correct: Varicose veins = valve defect.
• C. Incorrect: Stroke affects brain.
• D. Incorrect: Hypertension is unrelated.

Q8. Which of the following increases the risk of atherosclerosis?

A. High LDL cholesterol
B. High HDL cholesterol
C. Exercise
D. Omega-3 fatty acids

Answer: A

Explanation:

• A. Correct: LDL deposits fat in arteries.
• B. Incorrect: HDL removes cholesterol.
• C. Incorrect: Exercise prevents disease.
• D. Incorrect: Omega-3 lowers risk.

Q9. Stroke occurs due to:

A. Blockage of coronary artery
B. Blockage/rupture of brain artery
C. Valve malfunction
D. Kidney failure

Answer: B

Explanation:

• A. Incorrect: That’s heart attack.
• B. Correct: Stroke = ischemia or hemorrhage in brain.
• C. Incorrect: Valve defects cause murmurs, not stroke.
• D. Incorrect: Kidney failure not stroke.

Q10. Hemophilia is a disorder of:

A. High BP
B. Low RBC count
C. Blood clotting
D. Coronary arteries

Answer: C

Explanation:

• A. Incorrect: Not BP.
• B. Incorrect: That’s anemia.
• C. Correct: Hemophilia = clotting factor deficiency.
• D. Incorrect: Coronary artery narrowing is CAD.

Q11. Which condition is due to high WBC count (cancer of WBCs)?

A. Leukopenia
B. Leukemia
C. Polycythemia
D. Thrombocytopenia

Answer: B

Explanation:

• A. Incorrect: Leukopenia = low WBCs.
• B. Correct: Leukemia = uncontrolled proliferation of WBCs.
• C. Incorrect: Polycythemia = excess RBCs.
• D. Incorrect: Thrombocytopenia = low platelets.

Q12. Anemia is caused by:

A. Low WBC count
B. Low Hb or RBC count
C. High BP
D. Clotting factor deficiency

Answer: B

Explanation:

• A. Incorrect: WBCs not related.
• B. Correct: Anemia = low Hb/RBC → poor oxygen transport.
• C. Incorrect: Hypertension unrelated.
• D. Incorrect: That’s hemophilia.

Q13. Which genetic disorder of hemoglobin causes sickle-shaped RBCs?

A. Thalassemia
B. Sickle cell anemia
C. Hemophilia
D. Polycythemia

Answer: B

Explanation:

• A. Incorrect: Thalassemia = defective globin synthesis.
• B. Correct: Sickle cell anemia = Hb mutation → sickle RBCs.
• C. Incorrect: Hemophilia affects clotting.
• D. Incorrect: Polycythemia = excess RBCs.

Q14. Which disorder is common in people living at high altitudes?

A. Anemia
B. Polycythemia
C. Leukopenia
D. Hemophilia

Answer: B

Explanation:

• A. Incorrect: Anemia is deficiency, not altitude adaptation.
• B. Correct: Low oxygen stimulates RBC production → polycythemia.
• C. Incorrect: WBC count not altitude related.
• D. Incorrect: Hemophilia is genetic.

Q15. Which factor does NOT contribute to hypertension?

A. High salt intake
B. Stress
C. Obesity
D. Low physical activity
E. High HDL levels

Answer: E

Explanation:

• A. Incorrect: Salt raises BP.
• B. Incorrect: Stress raises BP.
• C. Incorrect: Obesity increases risk.
• D. Incorrect: Sedentary lifestyle increases risk.
• E. Correct: HDL protects against heart disease.

Q16. Which diagnostic test records electrical activity of the heart?

A. EEG
B. ECG
C. Spirometry
D. Angiography

Answer: B

Explanation:

• A. Incorrect: EEG = brain.
• B. Correct: ECG records heart activity.
• C. Incorrect: Spirometry = lung volumes.
• D. Incorrect: Angiography = blood vessels.

Q17. Which diagnostic test visualizes blood vessels using contrast dye?

A. ECG
B. Angiography
C. MRI
D. Ultrasound

Answer: B

Explanation:

• A. Incorrect: ECG = electrical signals.
• B. Correct: Angiography = x-ray with dye.
• C. Incorrect: MRI = soft tissues.
• D. Incorrect: Ultrasound = sound imaging.

Q18. Coronary bypass surgery is used to:

A. Cure anemia
B. Treat leukemia
C. Restore blood flow around blocked coronary artery
D. Increase RBC production

Answer: C

Explanation:

• A. Incorrect: Anemia treated with supplements.
• B. Incorrect: Leukemia needs chemotherapy.
• C. Correct: Bypass creates alternate path for blood.
• D. Incorrect: RBCs increased by erythropoietin.

Q19. Which vitamin deficiency causes prolonged bleeding time?

A. Vitamin A
B. Vitamin C
C. Vitamin K
D. Vitamin D

Answer: C

Explanation:

• A. Incorrect: Vision problems.
• B. Incorrect: Scurvy.
• C. Correct: Vitamin K → clotting factor synthesis.
• D. Incorrect: Vitamin D → bone health.

Q20. Which condition is treated with anticoagulant drugs like heparin?

A. Hemophilia
B. Thrombosis
C. Leukemia
D. Anemia

Answer: B

Explanation:

• A. Incorrect: Hemophilia already has clotting defect.
• B. Correct: Thrombosis (clot formation) treated with anticoagulants.
• C. Incorrect: Leukemia needs chemo.
• D. Incorrect: Anemia treated with iron/B12.

Q21. Edema occurs due to:

A. Increased osmotic pressure
B. Low plasma protein concentration
C. High RBC count
D. Increased oxygen levels

Answer: B

Explanation:

• A. Incorrect: Osmotic pressure prevents edema.
• B. Correct: Low albumin → less osmotic pull → fluid accumulates.
• C. Incorrect: RBC count not cause.
• D. Incorrect: O₂ levels not cause.

Q22. Rheumatic heart disease results from:

A. Viral infection
B. Autoimmune response after streptococcal infection
C. High cholesterol
D. Anemia

Answer: B

Explanation:

• A. Incorrect: Not viral.
• B. Correct: Streptococcal throat infection → antibodies damage valves.
• C. Incorrect: Cholesterol causes atherosclerosis.
• D. Incorrect: Anemia not related.

Q23. Which blood disorder is characterized by fragile RBCs and severe anemia?

A. Thalassemia
B. Leukemia
C. Polycythemia
D. Hemophilia

Answer: A

Explanation:

• A. Correct: Thalassemia = defective hemoglobin → fragile RBCs.
• B. Incorrect: Leukemia affects WBCs.
• C. Incorrect: Polycythemia = excess RBCs.
• D. Incorrect: Hemophilia = clotting disorder.

Q24. Which ion imbalance can cause arrhythmia?

A. Sodium
B. Calcium
C. Potassium
D. All of the above

Answer: D

Explanation:

• A. Correct: Na⁺ imbalance affects depolarization.
• B. Correct: Ca²⁺ affects contraction.
• C. Correct: K⁺ imbalance causes irregular rhythm.
• D. Correct: All important in arrhythmia.

Q25. Which lifestyle habit is the greatest risk factor for coronary artery disease?

A. Regular exercise
B. High-fiber diet
C. Smoking
D. Meditation

Answer: C

Explanation:

• A. Incorrect: Exercise prevents disease.
• B. Incorrect: High fiber lowers cholesterol.
• C. Correct: Smoking damages endothelium → CAD risk.
• D. Incorrect: Meditation reduces stress.

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