The heart is a muscular organ that functions as the central pump of the circulatory system, responsible for circulating blood throughout the body. Here’s a simplified explanation of how the heart works:
1. Blood Flow: Deoxygenated blood from the body returns to the heart through
veins and enters the right atrium.

2. Right Atrium: The right atrium contracts, pushing blood into the right ventricle
through the tricuspid valve.

3. Right Ventricle: The right ventricle contracts, pumping blood through the pulmonary valve into the pulmonary artery, which carries blood to the lungs for oxygenation.

4. Lungs: In the lungs, blood picks up oxygen and releases carbon dioxide.

5. Left Atrium: Oxygen-rich blood returns to the heart from the lungs through the pulmonary veins and enters the left atrium.

6. Left Ventricle: The left atrium contracts, pushing blood through the mitral valve into the left ventricle.

7. Aorta: The left ventricle contracts, pumping oxygenated blood through the aortic valve into the aorta, the body's largest artery.

8. Circulation: Blood travels through arteries, arterioles, and capillaries to deliver oxygen and nutrients to tissues throughout the body. Deoxygenated blood returns to the heart via veins to complete the cycle.

The heart’s rhythmic contractions (heartbeat) are coordinated by electrical impulses that ensure blood is pumped efficiently through the chambers and out to the body. This continuous process of circulation is vital for supplying oxygen and nutrients to cells and removing waste products like carbon dioxide.