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Lungs exchange carbon dioxide into oxygen

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Veins are blood vessels that carry blood to the heart

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a hollow muscular organ that pumps the blood through the circulatory system by rhythmic contraction and dilation.

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What is the purpose of the circulatory system ?

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What is the purpose of the circulatory system ?

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The circulatory system allows blood, nutrients, hormones, oxygen, and other stuff to cells

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The circulatory system consists of three independent systems that work together: the heart (cardiovascular), lungs (pulmonary), and arteries, veins, coronary and portal vessels (systemic).

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the system that circulates blood and lymph through the body, consisting of the heart, blood vessels, blood, lymph, and the lymphatic vessels and glands.