The Cardiac Cycle Flashcards
What is the cardiac cycle?
The sequence of events in one full beat of the heart.
What do the valves in the heart do?
Ensure that blood flows in the correct direction.
Why do the atrio-ventricular valves close?
The closure is caused by a swirling action of the blood around the valves when the ventricle is full.
When are the semilunar valves pushed open?
Once the pressure in the ventricles rises above the pressure in the major arteries, the valves are pushed open.
Why are the semilunar valves pushes shut?
They are pushed closed by the blood collecting in the pockets of the valves.
What is the pulse?
The pressure wave created by ventricular systole is what we can easily feel as the ‘pulse’.
How is blood pressure maintained in the aorta?
The elastic recoil of the walls helps to maintain the pressure.
Why is it important to maintain the pressure gradient between the aorta and the arterioles?
It is important to maintain the pressure gradient as this is what keeps the blood flowing towards the tissue.
