The heart is a muscular organ that pumps blood throughout the body, supplying oxygen and nutrients to tissues while removing waste products. It consists of four chambers: the two upper chambers, called atria, and the two lower chambers, known as ventricles. The heart's rhythmic contractions are controlled by electrical signals, ensuring efficient blood flow. Heart function is vital for maintaining overall health. The right atrium receives deoxygenated blood from the body and sends it to the right ventricle, which pumps it to the lungs for oxygenation. The left atrium receives oxygen-rich blood from the lungs and passes it to the left ventricle, which then distributes it to the rest of the body.