Platelets or thrombocytes are the cell fragments circulating in the blood, are produced by bone marrow, are involved in the cellular mechanisms of primary hemostasis leading to the formation of blood clots.
A normal platelet count in a healthy person is between 150,000 and 400,000 per mm≥ of blood.
Platelets provide the necessary hormones and proteins for coagulation. Collagen is released when the lining of a blood vessel is damaged. The platelet recognizes collagen and begins to work on coagulating the blood by forming a kind of stopper, so further damage to the blood vessel is prevented.
An abnormality or disease of the platelets is called a thrombocytopathy