The Blood Vessels

There are three types of blood vessels
  1. Arteries (colured red)
    These blood vessels carry the blood away from the heart,
    • in one circuit, to the lungs , and
    • in the other circuit, to the rest of the body
    2. Smaller arteries are called arterioles.
  2. Veins (coloured blue)
    These vessels carry blood back to the heart
    • from the lungs, and
    • from the body
    3. Large veins are called veins, smaller ones are called venules.
  3. Capillaries
    These very thin vessels, the diameter of a red blood cell, carry blood to individual cells, allowing nutrients and oxygen to be delivered, and wastes and carbon dioxide to be removed. They join the arterial system to the venous system.

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