Labels:daily | hakham OCR: VEIN VEIN is a vessel that carries oxygen- poor blood from parts of the body back to the heart. It has thinner walls than an artery because blood travels in vein lower pressure than does in an artery eins collect blood from tiny vessels in the body tissues called I capillaries. The capillaries merge with veins, which leave the tissues They merge again to form two main veins. the inferior and superior vena cava, that return blood to the heart. To help move blood towards the heart, veins have one way valves that prevent blood flow ring back the wrong way.
