List the steps in coagulation that occur on the platelet sur

List the steps in coagulation that occur on the platelet surface

Solution

Thanks for your query.

^{First of all, we have to know that the inner surface of the blood vessels are lines by atype of cell called the endothelium. whenever there is an injury on the skin, the blood vessesl below are cut or damaged. What this means is that the endothelium is broken down. this activates the process of coagulation which is nothing but the conversion of blood into a gel like clot which shuts down the bleeding or stops the loss of blood. when endothelium is damaged, the it releases collagen which helps bind the platelets to its surface through it s Ia/IIa receptors. Later the von willebrand factor is released which causes further tight binding of the platelet with the endothelium and collagen which is now beginnning to form the clot. this binding of collagen to the platelet surface releases integrins which promote further binding between platelets collagen and endothelium. The platelets then release the granules within them which contain TXA2, VW factor, ADP, serotonin whichactivate other platelets to join the clot.}

The granule s which are released increase calcium levels in the platelet. this activates protein kinase C which leads to the activation of Phospholipase A2. This produces changes in the cell membrane glycoprotein IIb/IIIa helping it to bind with fibrinogen. the platelets change shape and become stellate and the glycoprotein IIB/ IIIA forms links with collagen and help in adhering and collection of platelets.

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