Question

Which phase of the cardiac cycle happens when aortic valves are open explain

a) ejection
b) when pressure in left ventricle exceeds that in aorta
c) pressure gradient forces valve open

Answer 1

The aortic valves are open during the ventricular ejection phase of the cardiac cycle, which occurs when the left ventricular pressure exceeds the aortic pressure, forcing the valve open.

Step-by-step explanation:

The phase of the cardiac cycle when the aortic valves are open is known as the ventricular ejection phase. During this phase, the pressure within the left ventricle rises due to contraction of the ventricular muscle and exceeds the pressure in the aorta.

This pressure gradient between the left ventricle and aorta forces the aortic valve open, allowing blood to be ejected from the heart into the aorta. The ventricular ejection phase corresponds with ventricular systole, where the ventricles are contracting, and it is during this time that most of the blood is pumped out of the ventricles, constituting the stroke volume.