Question

when the left ventricle contracts, the ____ valve closes and the ____ valve is pushed open.

Explanation:

To solve this, we recall the cardiac cycle mechanics. When the left ventricle contracts (systole), the mitral (bicuspid) valve (between left atrium and left ventricle) closes to prevent backflow into the atrium. The aortic valve (between left ventricle and aorta) opens as ventricular pressure exceeds aortic pressure, allowing blood to eject into the aorta.

Answer:

mitral (or bicuspid); aortic