Question

How does blood gets coagulated on coming out from an injured vessel. How coagulation is normally prevented uninjured vessels.

Answer 1

Dear student,

The blood coming out from an injured vessel is coagulated to prevent excessive loss of blood from the body.

Following steps are involved in the coagulation or clotting process-

1. The mechanism of coagulation is activated by the platelets present in the blood by the stimulation of injury.
2. Thromboplastin from the injured vessel and blood platelet combines in the presence of calcium ion to form prothrombinase.
3. Prothrombinase converts the prothrombin into thrombin.
4. Thrombin converts fibrinogen to fibrin (soluble) through the process of fibrin.
5. The soluble fibrin is polymerized to form insoluble fibrin.

The insoluble fibrin is a dark reddish brown scum formed at the site of a cut or an injury which is a network of threads that trap dead and damaged formed elements of blood coming out from the injured vessel.

Regards,