The process of blood clotting has several stages:
1- Blood platelets are ruptured by the injury.
2- They release thromboplastin.
3- Thromboplastin turns prothrombin in thrombin.
4- Thrombin converts the liquid fibrinogen in solid fibrin fibres which create a web at the wound.
5. The blood cells caught in the web form a layer which slowly dries and creates a solid cloth that stops blood flow.
6. In a while a yellow liquid will come out of the clot’s periphery.