What is the primary function of the valve between the right atrium and right ventricle?

The primary function of the valve between the right atrium and right ventricle, known as the tricuspid valve, is to prevent backflow of blood. During the cardiac cycle, when the right ventricle contracts to pump blood into the pulmonary artery, the valve closes to ensure that blood does not flow back into the right atrium. This unidirectional flow is crucial for maintaining efficient circulation and ensuring that oxygen-poor blood moves toward the lungs for oxygenation without re-entering the atrium.

In contrast, regulating blood pressure involves factors such as the heart's output and the resistance of blood vessels rather than a specific valve function. Increasing heart rate is managed by the pacemaker cells in the heart, rather than a valve. Filtering blood is a function primarily associated with organs like the kidneys and does not relate directly to the function of the heart valves. Thus, the valve's role in preventing backflow is essential for maintaining proper circulation and cardiac efficiency.