During ventricular relaxation, what happens to the semilunar valves and the AV valves?

During ventricular relaxation, what happens to the semilunar valves and the AV valves?

• A. Semilunar valves close, AV valves open
• B. Semilunar valves open, AV valves close
• C. Semilunar valves close, AV valves close
• D. Semilunar valves open, AV valves open

Answer: (A)

During ventricular relaxation, the ventricles are in diastole and their pressure drops below that of the atria. This causes the atrioventricular (mitral and tricuspid) valves to open, allowing blood to flow from the atria into the ventricles. At the same time, the pressure in the aorta and pulmonary trunk remains higher than ventricular pressure, pushing the semilunar valves (aortic and pulmonary) closed to prevent backflow into the ventricles. So, the state is AV valves open and semilunar valves closed, which is why the correct choice reflects that combination.

During ventricular relaxation, the ventricles are in diastole and their pressure drops below that of the atria. This causes the atrioventricular (mitral and tricuspid) valves to open, allowing blood to flow from the atria into the ventricles. At the same time, the pressure in the aorta and pulmonary trunk remains higher than ventricular pressure, pushing the semilunar valves (aortic and pulmonary) closed to prevent backflow into the ventricles. So, the state is AV valves open and semilunar valves closed, which is why the correct choice reflects that combination.