Structure of Human Heart

The heart is a muscular organ with walls made of cardiac muscles. The coronary arteries supply nutrients and oxygen to the muscles while the coronary viens remove waste from the muscles.

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 The heart is divided into four chambers. the two upper chambers are called auricles or atria and the two lower chambers are called ventricles. The septum divides the heart into the right and left halves. The auricles have thinner walls than the ventricles. When the auricles contract, blood is pushed into the ventricles below. The left ventricle has a much thicker muscular wall than the right ventricle. The right ventricle pump blood to the lungs, which lie next to the heart. The left ventricle has pump blood from the heart to the rest of the body.

The right atrium is connected to the right ventricle by the tricuspid valve. The left atrium is connected to the left ventricle by the bicuspid or mitral valve. Semilunar valve are situated at the entrances of the aorta and the pulmonary artery to prevent the backflow of blood into the ventricles. The chordae tendineae prevent the valve from turning inside out when the ventricles contract.

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