Red blood cells, white blood cells, blood fluid and other components get stuck in the body wound and blood flow is stopped. This is called blood clotting or blood clotting. The process of blood clotting is called hemostasis. The steps in the process of hemostasis are:
1. Heparin and thrombomodulin inside blood vessels prevent blood from clotting. When a wound occurs anywhere in the body, blood flows out and the blood molecules at the wound site are broken by exposure to air. The platelets break down to form thromboplastin. Thromboplastin renders the heparin in the blood inactive or useless.
Wounded tissue ruptures and breakdown of microcirculation + air → thromboplastin
2. In the presence of calcium ions and factors VII, VIII, IX and X, thromboplastin converts the inactive prothrombin of the blood into active thrombin.
Thromboplastin + Ca++ + Prothrombin → Thrombin
3. Activated thrombin converts the blood fibrinogen protein into a fibrin formula.
Thrombin + fibrinogen → fibrin factor
4. The fibrin factor binds together to form a fibrin mesh. Fibrin mesh is a fibrin polymer.
Fibrin factor → fibrin meshwork
5. Red blood cells, white blood cells and blood fluid are trapped in the fibrin mesh. As a result, the blood flow stops and the blood clots. The blood clot appears reddish in color as the red blood cells get stuck.
Fibrin mesh + blood cell entrapment → blood clot
6. The enzyme plasmin breaks down the fibrin mesh as blood vessel remodeling begins. As a result, new tissue is formed. The wound gradually heals.