|an artery, capillary, or vein|
|circulating white blood cell, formed in bone marrow and in the spleen, that ingests cell debris|
|compound present in urine in small amounts|
blood vessel n.
An elastic tubular channel, such as an artery, a vein, a sinus, or a capillary, through which the blood circulates.
An elastic tube or passage in the body through which blood circulates; an artery, a vein, or a capillary.
a vessel in the human or animal body in which blood circulates. The vessels that carry blood away from the heart are called arteries, and their very small branches are arterioles. Very small branches that collect the blood from the various organs and parts are called venules, and they unite to form veins, which return the blood to the heart. Capillaries are minute, thin-walled vessels that connect the arterioles and venules; it is through the capillaries that nutrients and wastes are exchanged between the blood and body tissues. See artery; capillary; vein
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