What are the differences between arteries arterioles veins venues capillaries?

Answer 1

The Main Differences:Arteries:Arteries carry oxygenated blood, and are very narrow but thick, to enable them to maintain a high blood pressure, whilst also withstanding that pressure. Veins:Veins carry de-oxygenated blood, and are very dilate and thin, as they do not need to carry blood at such high pressures. Different Branches:Arteries and Veins:The circulatory system branches off into smaller and smaller parts.

Firstly the arteries and veins, the largest of the blood vessels, carry large volumes of blood to the necessary parts of the body.

Arterioles and Venules:These then branch off into arterioles and venules, which are smaller in diameter, and so carry smaller volumes of blood, however, they are more numerous. Arterioles and venules effectively surround the organs and tissues, to ensure that the whole of the organ/tissue can receive oxygen or remove carbon dioxide etc. Capillaries:These arterioles and venules then branch off into tiny capillaries, which are only thick enough to allow one red blood cell through at a time. This means that transport through the capillaries is slower, and there is more time for diffusion, osmosis etc. to take place.

The capillaries are even more numerous than the arterioles and venules, in fact, they are spread in between every few cells. This allows for effective diffusion between the blood and the tissue, as the substances do not have to travel very far.

The capillary walls are also only one cell thick, which allows for efficient diffusion, as the substances being transported do not have to travel very far.

Answer 2

arteries are big and veins are small