Circulation Mdcat Mcqs

 

HUMAN HEART MCQs

1. The human heart is enclosed in:

A) Pleura

B) Pericardium

C) Peritoneum

D) Meninges

Answer: B) Pericardium

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2. The septum separates:

A) Arteries and veins

B) Atria and ventricles

C) Right and left sides of heart

D) Valves and chambers

Answer: C) Right and left sides of heart

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3. Tricuspid valve is present between:

A) Left atrium & left ventricle

B) Right atrium & right ventricle

C) Left ventricle & aorta

D) Right ventricle & pulmonary artery

Answer: B) Right atrium & right ventricle

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4. Which part prevents backflow of blood into left ventricle?

A) Tricuspid valve

B) Bicuspid valve

C) Aortic semilunar valve

D) Pulmonary valve

Answer: C) Aortic semilunar valve

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5. The right ventricle pumps blood to:

A) Body

B) Lungs

C) Liver

D) Kidneys

Answer: B) Lungs

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CARDIAC CYCLE & HEARTBEAT MCQs

6. Duration of one cardiac cycle in a normal human is:

A) 0.5 sec

B) 0.8 sec

C) 1.2 sec

D) 2 sec

Answer: B) 0.8 sec

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7. The “lub” sound is produced by closure of:

A) Semilunar valves

B) AV valves

C) Aortic valve

D) Pulmonary valve

Answer: B) AV valves

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8. During ventricular systole:

A) Atria contract

B) Ventricles relax

C) Ventricles contract

D) All valves open

Answer: C) Ventricles contract

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9. Heartbeat is initiated by:

A) AV node

B) SA node

C) Bundle of His

D) Purkinje fibers

Answer: B) SA node

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10. The AV node delays impulse to:

A) Increase heart rate

B) Allow atria to contract fully

C) Stop blood flow

D) Relax ventricles

Answer: B) Allow atria to contract fully

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BLOOD VESSELS MCQs

11. Which vessel has the thickest wall?

A) Vein

B) Capillary

C) Artery

D) Venule

Answer: C) Artery

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12. Valves are present in:

A) Arteries

B) Veins

C) Capillaries

D) Aorta

Answer: B) Veins

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13. Exchange of materials occurs in:

A) Arteries

B) Veins

C) Capillaries

D) Venules

Answer: C) Capillaries

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14. Blood pressure is lowest in:

A) Arteries

B) Veins

C) Capillaries

D) Aorta

Answer: B) Veins

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15. Pulmonary artery carries:

A) Oxygenated blood

B) Deoxygenated blood

C) Mixed blood

D) Lymph

Answer: B) Deoxygenated blood

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LYMPHATIC SYSTEM MCQs

16. Lymph differs from blood in lacking:

A) RBCs

B) WBCs

C) Plasma

D) Platelets

Answer: A) RBCs

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17. Main function of lymph is:

A) Oxygen transport

B) Hormone secretion

C) Return tissue fluid to blood

D) Digest fats

Answer: C) Return tissue fluid to blood

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18. Lymph nodes are important for:

A) Pumping blood

B) Filtration of lymph

C) Oxygen transport

D) Clotting

Answer: B) Filtration of lymph

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19. Lacteals are involved in absorption of:

A) Proteins

B) Glucose

C) Fats

D) Minerals

Answer: C) Fats

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20. Lymphatic system helps in:

A) Circulation of blood

B) Defense against pathogens

C) Digestion

D) Respiration

Answer: B) Defense against pathogens

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