Heart Anatomy and Physiology

The heart is a muscular organ about the size of a fist that pumps blood throughout the body. It has four chambers: two upper atria and two lower ventricles. Blood enters the heart through the atria, then moves to the ventricles, which pump it out to the lungs for oxygen or to the rest of the body. The heart's rhythmic contractions are controlled by electrical signals, ensuring steady blood flow. Valves between chambers prevent backflow, maintaining efficient circulation. Overall, the heart's coordinated activity supplies oxygen and nutrients vital for every part of the body to function properly.