Q. Which of the statements are CORRECT about joint diastole?
a. Bicuspid and tricuspid valves are open
b. Bicuspid and tricuspid valves are closed
c. Semilunar valves are open
d. Semilunar valves are closed

 2966  229 NTA AbhyasNTA Abhyas 2020Body Fluids and Circulation Report Error

Solution:

The cardiac cycle begins with joint diastole. This means auricles and ventricles are in a relaxed position. This causes auriculoventricular valves (tricuspid and bicuspid valves) to open. Since ventricles are in relaxed position there is no pressure on semilunar valves and hence are closed. Thus blood from pulmonary veins and vena cava flows into left and right auricles and thus enters the ventricles. No blood flows out of the ventricles.