Missouri University of Science and Technology tuition is $7,734 per year for in-state residents. This is 13% more expensive than the national average public four year tuition of $6,841. The cost is 53% cheaper than the average Missouri tuition of $16,299 for 4 year colleges.
Systole: Period of ejection. AV valves closed Semilunar valves opened AV valves closed Semilunar valves closed Diastole: Period of isovolumic relaxation. Blood flowing back toward the relaxed ventricles causes the semilunar valves to close, which is the beginning of ventricular diastole.
The high blood pressure in the aorta holds this valve shut tight. A pressure greater than the one holding any vavle shut is required to open it, ie the ventricular presure must be greater than the aortic pressure is required to force the aortic valve open.