The figure below shows the mechanism of blood clotting.
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- When a blood vessel is damaged, platelets will gather around the wound and coagulate.
- At the same time, an enzyme called thrombokinase will be released.
- Thrombokinase will convert the inactive prothrombin to the active thrombin.
- The thrombin will then catalyses the soluble fibrinogen to the insoluble fibrin.
- Fibrin will form a fibrous network to trap the blood cells and form the blood clot.