Scanning electron micrograph of an unactivated blood platelet. Platelets (thrombocytes) are small, non-nucleated cells formed in the bone marrow, and

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Scanning electron micrograph of an unactivated blood platelet. Platelets (thrombocytes) are small, non-nucleated cells formed in the bone marrow, and are present in circulating blood in large numbers. Their shape in an unactivated state is round or oval (2-3 micrometres diameter), as here; activated platelets have dendritic processes, or pseudopodia. Platelets function in 2 ways. Firstly, they help plug small defects in the walls of small blood vessels: secondly, they are involved in clotting & also release serotonin, which reduces blood flow by constricting the damaged vessels. Magnification: x53,000 at 8x10inch size.

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Size: 5394px × 3584px
Photo credit: © NIBSC/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, blood, body, clotting, human, platelet, platelets, thrombocyte, unactivated