The primary function of the heart in the human body is to pump blood throughout the circulatory system. This vital organ ensures that oxygenated blood reaches tissues and organs, while also circulating deoxygenated blood back to the lungs for reoxygenation. The heart consists of four chambers: the right and left atria and the right and left ventricles, which work rhythmically to maintain circulation. It plays a critical role in delivering nutrients, hormones, and immune cells to various parts of the body, while also aiding in the removal of waste products. The heart is essential for sustaining life and supporting overall health.