The vessels designed for the return trip are your ... Veins make up a network of connecting tubes throughout the human body, ranging in size from 1 mm (about the size of a pencil point) to 2 ...

Blood travels around the body in tubes called arteries, veins or capillaries Arteries carry blood away from the heart towards an organ Veins carry blood from an organ towards the heart.

Your coronary arteries are two major blood vessels ... is when you get a blood clot in a vein deep in your body. This usually happens in your lower leg, thigh, or in your groin.

Vaping has an immediate effect on how well the user’s blood vessels work, even if the e-cigarette doesn’t contain nicotine, according to new research.