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

The primary function of the right atrium and right ventricle is to pump blood into the lungs for oxygenation. The right atrium receives deoxygenated blood from the body through the superior and inferior vena cavae. Once filled, it contracts to send this blood into the right ventricle, which then contracts to propel the blood through the pulmonary artery into the lungs. This process is vital because it allows for gas exchange, where carbon dioxide is removed from the blood and oxygen is picked up.

In contrast, the other options do not accurately reflect the roles of the right atrium and right ventricle. These chambers are not involved in receiving oxygen-rich blood from the body, as that function is attributed to the left atrium. The right ventricle does not pump blood to the aorta; that responsibility falls to the left ventricle, which sends oxygen-rich blood to the body. Additionally, while blood circulation does occur within the heart, stating that this is the primary function oversimplifies the critical role of the right atrium and ventricle in pulmonary circulation.