#75 Blood clotting

When an injury causes a blood vessel wall to break, platelets are activated. They change shape from round to spiny, stick to the broken vessel wall and each other, and begin to plug the break. 














The platelets also interact with fibrinogen, a soluble plasma protein, to form insoluble fibrin. Calcium is required for that. 

Fibrin strands form a net that entraps more platelets and other blood cells (red cells and white cells), producing a clot that plugs the break.

Necessity for blood clotting  

• Prevent excessive blood loss from the body when there is a damage of the blood vessel.
• Maintain the blood pressure.
• Prevent the entry of microorganism and foreign particles into the body.
• Promote wound healing.