1) through which structure is transported the blood a) heart b) blood vessels c) lungs d) stomach 2) through which organ of the circulatory system pumps the blood a) arteries b) veins c) heart d) blood 3) what are the vessels through which the blood goes a) cells b) lungs c) heart d) arteries, veins 4) how many parts does the heart have a) 4 b) 1 c) 3 d) 6

circulatory system

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