Second-line response: Blood Clotting and Wound Repair

Name the 4 second-line responses?

1. Blood clotting
2. Inflammation
3. Wound repair
4. Phagocytosis

Explain the steps of blood clotting.

1. There is an open wound.
2. Serotonin and prostaglandins are released to narrow the blood vessel. This reduces blood flow to the affected area.
3. Clotting factors are activated and the platelets form a plug on the wound.
4. Prothombrin is convererted to thromin using enzyme thromboplastin and Ca2+ ions.
5. Thrombin triggers the conversion of fibrinogen into fibrin.
6. Fibin forms a mesh. Platelets and blood cells join this to form an insoluble clot on the wound.

Explain the steps of wound repair.

1. Large defect is filled by the fibrin clot.

2. New blood vessels begin to form. There is granulation tissue growing from the epidermic, which becomes fibrin.

3. Collagen lays on the epidermis. Stem cells differentiate into epithelial cells.

4. Collagen matures and achieves structural integrity which allows the regrowth of the epidermis.

5. Contractile cells pull the would together.

6. Unwanted cells die.

Describe the blood clotting process. \[4\]