What is the primary function of the right atrium in the heart?

The primary function of the right atrium is to receive deoxygenated blood from the body. This blood enters the right atrium through two large veins, the superior vena cava and the inferior vena cava. After filling the right atrium, the blood moves through the tricuspid valve into the right ventricle, where it is then pumped to the lungs for oxygenation.

Understanding the role of the right atrium is crucial for grasping the overall circulation process of the heart. While the other choices describe functions related to different parts of the cardiac cycle, the specific role of the right atrium is to act as a receiving chamber for deoxygenated blood before it travels to the lungs.