Question

How does the blood flow through heart during cardiac cycle​

Answer 1

At the beginning of the cardiac cycle, both the atria and ventricles are relaxed (diastole). ... Blood flows into the left atrium from the four pulmonary veins. The two atrioventricular valves, the tricuspid and mitral valves, are both open, so blood flows unimpeded from the atria and into the ventricles.

I think its because I found it in a book of class 9