Following an injury, our body goes through a complex process to repair the wound. Specific types of blood cells and a protein called fibrin (which is involved in blood clotting) dry out to form a cap or scab over the wound. The role of the scab is to protect the inside of the wound from infection while the wound undergoes repair. Fibroblasts under the scab release collagen and growth factors. The growth factors turn the cells from stationary to migratory cells so that they can join the separated parts of skin together.