Question

Which phase of the cardiac cycle involves the closure of both the AV valves and the semilunar valves, leading to an increase in pressure within the ventricles?

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

Answer 1

The phase of the cardiac cycle that involves the closure of both the AV valves and the semilunar valves, leading to an increase in pressure within the ventricles is ventricular systole.

Step-by-step explanation:

The phase of the cardiac cycle that involves the closure of both the AV valves and the semilunar valves, leading to an increase in pressure within the ventricles is ventricular systole.

During ventricular systole, the muscles in the ventricles contract, causing the pressure of the blood within the chamber to rise. This increase in pressure closes the atrioventricular valves (the tricuspid and mitral valves) and the semilunar valves, preventing backflow of blood into the atria and ensuring that blood is ejected out of the heart.

Therefore, the correct answer is Ventricular systole (Option B).