Question

What are the two phases during systole? What is open/closed?

a) Isovolumetric contraction (both valves closed) and ejection (aortic valve open)
b) Rapid ejection (both valves open) and reduced ejection (mitral valve closed)
c) Isovolumetric contraction (mitral valve open) and isovolumetric relaxation (aortic valve open)
d) Reduced ejection (mitral valve closed) and rapid ejection (aortic valve open)

Answer 1

The two phases during systole are isovolumetric contraction and ejection. In isovolumetric contraction, both the atrioventricular and semilunar valves are closed, and no blood is being ejected from the ventricles. In the ejection phase, the aortic valve is open while the atrioventricular valves are closed, allowing blood to be pumped out of the heart.

Step-by-step explanation:

The two phases during systole are isovolumetric contraction and ejection. During isovolumetric contraction, both the atrioventricular and semilunar valves are closed, so no blood is being ejected from the ventricles. In the ejection phase, the aortic valve is open while the atrioventricular valves are closed, allowing blood to be pumped out of the heart.