All of the body’s organs require blood for good function. Blood is composed of a liquid portion known as plasma and several cell components. The cell components are red blood cells, white blood cells and platelets. The red blood cells are the cells that carry oxygen to the body’s organs. The blood vessels that carry the oxygen-rich blood to the organs are known as arteries. During the process of metabolism the organs develop carbon dioxide. As the oxygen-rich blood passes through the organ, the oxygen in the red blood cells is exchanged for the carbon dioxide. Blood rich is oxygen is a bright red, whereas (в то время как) blood that has had the oxygen extracted is a dark red to purple (пурпурный) color. The blood that has had its oxygen extracted is known as de-saturated (saturated – насыщенный) blood. The blood vessels that carry the de-saturated blood away from the organ are known as veins. The heart pumps nonstop and supplies your body with blood that is rich in oxygen. For its job, your heart needs its own oxygen-rich blood supply. Blood gets oxygen from the lungs and travels to your heart through the coronary arteries. A large vessel called the aorta carries blood from your heart to the rest (остальной) of your body. The coronary arteries branch off from the aorta. Smaller arteries branch off from the coronary arteries. These smaller arteries run over and through the heart muscle. They nourish (питать) every part of the heart with blood.
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| Ex. 32. Translate the sentences. Pay attention to the meanings of FOLLOW. | | | Text G. The heart valves |