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blood vessels that carry waste containing blood from the tissues back to the heart
blood vessels that carry blood away from the heart
tiny, thin-walled blood vessels that allow the exchange of gases and nutrients between the blood and the cells of the body
iron-containing protein in red blood cells that carries oxygen for delivery to cells
pathway of circulation between the heart and the lungs
pathway of circulation between the heart and the rest of the body except the lungs
flap of connective tissue between an atrium and a ventricle, or in a vein, that prevents backflow of blood
red blood cells
blood cells containing hemoglobin that carry oxygen through the bloodstream
white blood cells
cells that police the body by destroying foreign materials
tiny, disk-shaped bodies in the blood, important in blood clot formation