Question

Which event during the cardiac cycle is associated with the occurrence of "DUB" and the situation where the pressure in the aorta is greater than in the left ventricle?

A) Atrial systole
B) Ventricular systole
C) Ventricular diastole
D) Atrial diastole

Answer 1

The 'DUB' sound in the cardiac cycle is associated with ventricular diastole, which occurs when the semilunar valves close as the pressure in the aorta surpasses the pressure in the left ventricle.

Step-by-step explanation:

The event during the cardiac cycle associated with the occurrence of the 'DUB' sound is C) Ventricular diastole. This sound is produced when the semilunar valves (pulmonary and aortic valves) close due to the pressure in the aorta becoming greater than the pressure in the left ventricle, preventing backflow of blood into the ventricle. The closure of these valves marks the end of ventricular systole and the beginning of ventricular diastole, where the ventricles relax and the heart fills with blood again.