Dear student,
Coagulation also known as clotting is defined as the process by which blood changes from a liquid form to a gel thus forming a blood clot over an injury. This clot is mainly formed from the network of threads called fibrins in which dead and damaged formed elements of blood are trapped. Fibrins are formed by the conversion of inactive fibrinogens in plasma by enzyme thrombin. Thrombin is formed by another inactive substance called prothrombin which is present in plasma and this conversion is due to the enzyme called thrombokinase. An injury or trauma stimulates the platelets in the blood to release certain factors which activate the mechanism of coagulation. Calcium ion play a very important role in the process of clotting.
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