Blood is normally contained within the circulatory system: the heart, arteries, capillaries and veins. When these are torn or damaged, bleeding occurs. This can be on the outside of the body through a visible wound or on the inside of the body (internal bleeding).Blood carries oxygen from the lungs to the heart along the arteries to the tissues and through the tissues in the capillaries where the oxygen is made available for use. Veins carry the deoxygenated blood back to the heart.
Types of bleeding