Which chambers of the heart are referred to as the lower chambers?

The lower chambers of the heart are specifically known as the ventricles. In this case, the right ventricle and the left ventricle are responsible for pumping blood out of the heart. The right ventricle sends deoxygenated blood to the lungs for oxygenation, while the left ventricle pumps oxygenated blood to the rest of the body. This function is critical for maintaining circulation and ensuring that oxygen-rich blood is delivered to tissues and organs.

In contrast, the atria, which include the right atrium and left atrium, are the upper chambers that receive blood returning to the heart. Their role is primarily to collect blood and prepare it for the ventricles, which then carry out the more forceful work of pumping blood out of the heart. Understanding the distinction between the upper and lower chambers is essential for grasping the overall mechanics of the cardiovascular system.