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granular leukocyte

(GRAN-yoo-lur LOO-koh-site)
A type of immune cell that has granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma. Neutrophils, eosinophils, and basophils are granular leukocytes. A granular leukocyte is a type of white blood cell. Also called granulocyte, PMN, and polymorphonuclear leukocyte.
Blood cell development; drawing shows the steps a blood stem cell goes through to become a red blood cell, platelet, or white blood cell. A myeloid stem cell becomes a red blood cell, a platelet, or a myeloblast, which then becomes a granulocyte (the types of granulocytes are eosinophils, basophils, and neutrophils). A lymphoid stem cell becomes a lymphoblast and then becomes a B-lymphocyte, T-lymphocyte, or natural killer cell.Enlarge this image in new window
Blood cell development. A blood stem cell goes through several steps to become a red blood cell, platelet, or white blood cell.
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