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Cardiovascular Health

Describe the structure of a vein?

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November 28, 2009 2:29PM

Veins carry deoxygenated blood to the heart. To do this they have multiple structural features.

The first feature is the wide lumen. This is because it takes blood back to the heart so a high pressure is not required. It also allows ease of flow.

The second feature is the endothelium that surround the lumen. The endothelium is known as a lining and is a single layer of cells. This reduces friction of the flowing blood.

The third feature of the vein is that it has valves. Valves are very useful as it keeps blood flowing towards the heart and prevents backflow.

The forth feature of the vein is that it has smooth muscle. Smooth muscle can constrict to improve exchange of gas at the alveoli.

The fifth feature of the vein is that it has elastic tissue which works as the smooth muscles relaxes to return the vessel to it's orignal size and shape.

Lastly as the previous answer stated: the walls of the vein are thin as there is little muscle.