MICROANATOMY

Detailed explanation-1: -Tricuspid valve: Allows blood to pass from the right atrium to the right ventricle; prevents blood from flowing back into the right atrium as the heart pumps (systole).

Detailed explanation-2: -The atrioventricular valves prevent backflow of blood into the atria during ventricular contraction (systole), and the aortic/pulmonic (semilunar) valves prevent backflow of blood into the ventricles during ventricular relaxation (diastole).

Detailed explanation-3: -As the ventricles contract, ventricular pressure exceeds arterial pressure, the semilunar valves open and blood is pumped into the major arteries. However, when the ventricles relax, arterial pressure exceeds ventricular pressure and the semilunar valves snap shut.