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Explain how the human heart, lungs, and circulatory system work together to keep us alive
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First, your diaphragm expands allowing empty space created by the diaphragm expanding to be filled with air rushing in from your mouth and down your trachea into your bronchi and then to your bronchioles so oxygen can be diffused into the capillaries lining you alveoli. The oxygen diffused into your capillaries continues into venules and then to your pulmonary vein into your left atrium and then into the left ventricle of the heart to be transported throughout the body by the aorta and then other arteries to other organs and tissues of the body. Some of the organs it goes to cleans the blood out such as the kidneys and spleen and the blood also goes to the cells in the body and provides them with oxygen and other things while taking the waste product carbon dioxide from the cells to be sent out of the body through the lungs.
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In order to stay alive, the body's cells need oxygen delivered, and carbon dioxide removed.. . The blood is the transport vehicle for those molecules. The heart pumps the blood around, and the circulatory system (arteries, veins, capillaries, etc.) gets the blood where it needs to go.. . The lungs are where the body takes oxygen in and lets carbon dioxide off. We breathe air in, which has more oxygen in it than our venous blood does. By diffusion, oxygen molecules pass from our alveoli (air sacs in the lungs) into pulmonary capillaries. There is very little carbon dioxide in the air, so it diffuses out of the blood into the alveoli, and we breathe it out.. . How's that?
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