The Structure and Function of the Heart

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The Structure and Function of the Heart The heart is a muscular organ that works continuously throughout the lifetime or an organism; it lies in the thoracic cavity behind the sternum. The human heart is two pumps side by side, separated by the septum, the left side of the heart deals with the oxygenated blood which comes from the lungs, and the right side deals with the deoxygenated blood which comes from the body. Each pump has two separate chambers; the atrium has thin walls and elastic, which stretches as it collects the blood. The ventricle has a thicker muscular wall, as it has to pump the blood a longer distance, to the lungs or the rest of the body whereas the atrium only has to pump it to the ventricle. The right ventricle only has to pump blood to the lungs, which are only a short distance away compared to the left ventricle, which has to pump blood to the extremities of the body. Because of this, the right ventricle has a thinner muscular wall enabling it to create more pressure to push the blood further. Valves separate the atrium and ventricle, in order to prevent the backflow of blood when the ventricles contract. There are two sets of valves; the atrioventricular (bicuspid) valves which are formed of two cup-shaped flaps on the left side of the heart, and the right atrioventricular (tricuspid) valves, which are formed of three cup-shaped flaps on the right side of the heart. Blood is taken to each of the four chambers of the heart by large blood vessels; vessels connecting the heart to the lungs are called pulmonary vessels. The aorta is connected to the left ventricle and carries oxygenated blood to all parts of the body (excluding the lungs, the vena cava is connected to the right atrium and brings deoxygenated blood back from the tissues of the body. The pulmonary artery is connected to the right ventricle and carries deoxygenated
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