When a cut or other damage ruptures a blood vessel, the blood inside it is released and the liquid flows out. If an artery is cut, the force of pressure from the heart causes it to gush out in large spurts and immediate medical attention is required. Bleeding from veins is slower, but excessive blood loss is still dangerous so the blood must be stopped.
The body's own mechanism to stop too much blood being lost involves blood clotting. At the point of the cut in the skin, a mesh is formed that traps blood cells and prevents further blood escaping. It is important that blood only clots when it should - if a blood clot forms inside the body this can cause problems.
Sometimes, the rough surface of the inside of arteries sets off the clotting process and clots form inside the blood vessels that lead to the heart muscle, causing a heart attack.
The body's own mechanism to stop too much blood being lost involves blood clotting. At the point of the cut in the skin, a mesh is formed that traps blood cells and prevents further blood escaping. It is important that blood only clots when it should - if a blood clot forms inside the body this can cause problems.
Sometimes, the rough surface of the inside of arteries sets off the clotting process and clots form inside the blood vessels that lead to the heart muscle, causing a heart attack.