What valve separates the right atrium from the right ventricle?

The valve that separates the right atrium from the right ventricle is the tricuspid valve. This valve is crucial for directing blood flow within the heart and ensuring proper circulation. It is named "tricuspid" because it has three leaflets, which help prevent backflow of blood when the ventricles contract.

During the cardiac cycle, the tricuspid valve opens to allow deoxygenated blood to flow from the right atrium into the right ventricle. When the ventricle contracts to pump blood into the pulmonary artery—leading to the lungs for oxygenation—the tricuspid valve closes securely to prevent blood from flowing back into the atrium. This action is essential for maintaining efficient blood flow through the heart and the overall circulatory system.