Which of the following refers to an organ of circulatory system that is responsible for pumping the throughout the body?

A. Arteries

B. Heart

C. Veins

D. Cappilaries


Which heart valves are NOT actively closed by the contraction of muscular structures?

A. Mitral valves

B. Semilunar valve

C. Atrioventricular valves

D. Tricuspid valves