What is the main function of the AV valves

What is the main function of the AV valves?A) To prevent the flow of blood from atria to ventricles during atrial systoleB) To prevent the flow of blood from atria to ventricle during the quiescent periodC) To prevent the flow of blood from ventricles to atria during ventricular ejectionD) To prevent the flow of blood from arteries back into the ventricles during isovolumetric relaxation2) During atrial systole, which of the following pressure gradients exist?A) Higher pressure in atria compared to ventriclesB) Higher pressure in ventricles compared to atriaC) Higher pressure in ventricles compared to arteriesD) Same pressure in atria and ventricles3) In the heart, blood will flow from areas of low pressure to areas of high pressure.A) TrueB) False4)Which stage of the cardiac cycle helps to fill ventricles to maximum blood volume?A) Quiescent periodB) Atrial systoleC) Ventricular ejectionD) Isovolumetric relaxation5)During the quiescent period, blood is ONLY filling the atria (not the ventricle).True or False