Atrial Systole -
Blood enters from the vena cava, the right atrial muscle contracts, and the right AV valve opens due to the PRESURE DIFFERENCE.
Ventricular Systole -
Blood enters the right ventricle. The right ventricle muscle contracts, forcing the SEMI - LUNAR valves open in the pulmonary artery. Blood leaves through artery and enters the lungs
The atria and ventricles relax. Elastic recoil of…