What is the name of the upper chamber of the heart?

The upper chamber of the heart is called the atrium. The heart consists of four chambers: right atrium, left atrium, right ventricle, and left ventricle. The atria are responsible for receiving blood from the body (right atrium) or the lungs (left atrium) and then passing it down to the ventricles, which are the lower chambers that pump the blood out of the heart.

Understanding the atrium's role is crucial in the circulatory system; it acts as a reservoir that collects blood before it enters the ventricles. This process ensures that the ventricles can effectively manage the flow of blood to the lungs for oxygenation and to the rest of the body.

Other terms in the question refer to different structures related to the heart: ventricles are the lower chambers that pump blood out, the aorta is the major artery that carries oxygenated blood from the heart to the body, and valvules refer to the small valves that help regulate blood flow between the chambers. Each of these plays an important role in the overall function of the heart, but they do not specifically describe the upper chambers.