Body & HealthHow it works
How your blood switches from liquid to solid in seconds.
First platelets stick to the injury and form a soft plug. In parallel a cascade of 13 numbered factors runs, ending in thrombin. Thrombin turns dissolved fibrinogen into fibrin threads, and factor XIII cross-links them. Each step activates many of the next – which amplifies the signal enormously.
Useful: A cascade is an amplifier: a tiny trigger produces a large, fast response.
Source: en.wikipedia.org