Here's how it works:

* Fibrinogen is a soluble protein found in blood plasma.

* When a blood vessel is damaged, a cascade of events is triggered, ultimately activating thrombin, an enzyme.

* Thrombin cleaves fibrinogen, converting it into fibrin.

* Fibrin is an insoluble protein that forms a mesh-like structure, trapping blood cells and platelets to form a clot.

This process is essential for stopping bleeding and preventing further blood loss.