___ Insoluble fibrous protein involved in the clotting of blood.

Clotting of blood:

• Clotting or coagulation of blood involves the conversion of liquid blood into a jelly-like substance when the blood vessels get damaged.
• The jelly-like substance, when mixed with RBCs, forms a blood clot.

Fibrin:

• Fibrin is the insoluble fibrous protein formed from fibrinogen, a soluble protein.
• Fibrin forms a mesh-like or jelly-like substance at the injury site and ultimately, the blood clot is formed when the red blood cells get entangled with the mesh-like substance.