Which valve separates the left atrium and left ventricle?

• A. Tricuspid valve
• B. Aortic valve
• C. Pulmonary valve
• D. Mitral valve

Answer: (D)

Valves in the heart ensure one-way blood flow between chambers. The valve between the left atrium and left ventricle is the mitral valve, also known as the bicuspid valve. It has two cusps that open to allow oxygen-rich blood to move from the left atrium into the left ventricle during diastole, and it closes during systole to prevent backflow into the atrium. This position is what distinguishes it from the other valves: the tricuspid valve sits between the right atrium and right ventricle; the pulmonary valve lies between the right ventricle and the pulmonary artery; the aortic valve sits between the left ventricle and the aorta. The mitral valve is essential for efficient circulation on the left side of the heart.