Platelets are disk shaped and assist in clotting the blood, the mechanism that stops bleeding. There are three types of bleeding. Venous bleeding is dark red or maroon, the blood flows in a steady stream. Arterial bleeding is life threatening and difficult to control. In small wounds, only the capillaries are damaged.
Deeper wounds result in damage to the veins and arteries.
Damage to the capillaries is usually not serious and can easily be controlled with a Band-Aid. Damage to the veins and arteries are more serious and can be life threatening. A loss of 2 pints may cause shock, a loss of 5 to 6 pints usually results in death. During certain situations it will be difficult to decide whether the bleeding is arterial or venous. The distinction is not important.