In isovolumetric ventricular contraction, both AV valves and semilunar valves are closed. Question 10Answera.Trueb.False

Answer

The correct answer to the question is a. True.

Explanation

In isovolumetric ventricular contraction, the ventricles contract with no change in volume. This occurs because both the atrioventricular (AV) valves and the semilunar valves are closed during this phase of the cardiac cycle. The closure of the AV valves prevents blood from flowing back into the atria, while the semilunar valves remain closed until the pressure in the ventricles exceeds that in the aorta and pulmonary artery, allowing for ejection of blood. This unique phase highlights the importance of pressure changes in the heart's function while maintaining a constant volume of blood within the ventricles.