Question

fill in the blank question
as the cardiac cycle begins, the semilunar valves are closed because the pressure exerted by the blood in the ventricles is than the pressure the blood exerts in the great arteries.
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Explanation:

Semilunar valves open when ventricular pressure exceeds arterial pressure and close when ventricular pressure is lower than arterial pressure. At the start of the cardiac - cycle, the semilunar valves are closed because ventricular pressure is lower than arterial pressure.

Answer:

lower