develops from myeloid cell promyelocyte granulocytopoietic cell myelocyte 2010-08-30T01:08:19Z A cell type that is the first of the maturation stages of the granulocytic leukocytes normally found in the bone marrow. Granules are seen in the cytoplasm. The nuclear material of the myelocyte is denser than that of the myeloblast but lacks a definable membrane. The cell is flat and contains increasing numbers of granules as maturation progresses. BTO:0000734 FMA:83525 cell tmeehan