For example, a capillary is microscopically thin to allow gases to exchange, the arteries are tough and flexible to cope with high pressure blood flow and the veins contain valves to prevent the ...

Actually, they aren't. People think they're blue because that's often how they appear in diagrams and illustrations. But that's just to set them apart from the bright red arteries. The veins on the ...

The vessels that feed the heart are called coronary arteries (shown in the diagram right) and they branch off from ... A healthy artery in your chest may be used, or veins from your leg can be taken ...

Every possible part of the body has to be supplied with oxygen and food and water, and the veins and arteries are like roads going all the way through your body with the blood cells like delivery ...