Topic 17-Blood Vessels: Arteries, Veins, & Capillaries-Jgoldberg






Blood VesselsThere are three types of blood vessels. They are the arteries, veins, and capillaries. Below will tell you about them more in dept
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Arteries
The blood flow in the arteries flows away from the heart. It has the thickest walls out of the two other blood vessels which are the veins and the capillaries. It has no valves. The blood pressure inside of the arteries is high. The function of the artery is to carry oxygen rich blood from the heart to the body. The walls of the arteries are also elastic
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Veins
The blood flow in the veins flow towards the heart. The walls in the veins are thinner than the walls in the artery but thicker than the capillaries. The veins are the only blood vessels that have valves. The blood pressure in the veins is low. They carry oxygen low blood to the heart so it can go to the lungs to get more oxygen. The walls in the veins are not only thinner but the pathway inside them is more narrow.

Capillaries
In the capillaries the blood flows both towards and away from the heart. The capillaries have the thinnest cell wall out of all the blood vessels. It is only one cell thick. There are also no valves in a capillary. In a capillary the blood pressure is low. The capillaries alow oxygen and nutrients to diffuse from the blood into the tissues and carbon dioxide and other wast products to move from the tissues into the blood.


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