Blood vessels.

Arteries are any of the muscular-walled tubes forming part of the circulation system by which blood (mainly that which has been oxygenated) is conveyed from the heart to all parts of the body.

Capillaries are any of the fine branching blood vessels that form a network between the arterioles and venules. A

 tube that has an internal diameter of hairlike thinness.

 Veins are any of the tubes forming part of the blood circulation system of the body, carrying in most cases oxygen-depleted blood towards the heart.

Blood: Your blood is made up of 54% Plasma, 45% Red blood cells and 1% white blood cells and platelets.

Plasma is a straw coloured liquid that transports carbon dioxide from your cells to your lungs, nutrients from the small intestine to your cells and chemical messengers (hormones) to your cells.

Red blood cells contains a chemical called haemoglobin that carries oxygen around your body.

White blood cells are responsible for fighting infection and disease. the number of white blood cells increase when a person is fighting an infection or disease.

Platelets are tiny fragments of cells. they are reasonable for making blood clot when you cut your skin.