Question

Choose the correct answer from each of the four options given below-

The second heart sound (dubb) is associated with the closure of-

• A. Tricuspid valve
• B. Semilunar valves
• C. Bicuspid valves
• D. Tricuspid and bicuspid valves

Answer 1

The correct option is B

Semilunar valves

The correct option is B.

Explanation for the correct option:

1. The semilunar valves are located between the ventricles and their respective exiting blood vessel.
2. During the start of ventricular diastole, the ventricles relax and the semilunar valves close in order to prevent the blood from flowing into the vessels.
3. This causes the second heart sound dubb.

Explanation for the incorrect options:

1. The bicuspid and tricuspid valve is located between the atria and ventricles of the heart.
2. During the start of ventricular systole, the ventricles contract, bicuspid and tricuspid valves close, and the semilunar valves open.
3. This causes the first heart sound lubb.

Final answer: The second heart sound (dubb) is associated with the closure of semilunar valves.