Question

what are the functions of platelets in the blood?
are functions of a scab are the same as of platelets in blood?

Answer 1

The primary function of blood platelets is to prevent bleeding. Without blood platelets, merely scratching can make one bleed to death.

Answer 2

lanre is correct - platelets are important for clot formation which prevents excessive blood loss. Platelets also provide growth factors which are important in wound healing. Examples include Platelet - derived growth factor (PDGF) and transforming growth factor beta (TGFbeta). PDGF makes cells move (chemotaxis) whilst TGFbeta promotes extracellular matrix production. You can imagine both processes taking place during wound healing. Hope this is OK