Dictionary > Granulocyte

Granulocyte

Definition
noun, plural: granulocytes
A leukocyte characterized by the presence of numerous staining granules in the cytoplasm when observed by light microscopy
Supplement
White blood cells (also called leukocytes) are cells of the immune system. They are called white due to the lack of the hemoglobin pigment, which is present in red blood cells. Similar to red blood cells though, the white blood cells also came from a hematopoietic stem cell (hemocytoblast). The hemocytoblast gives rise to progenitor cells of both the myeloid series and the lymphoid series. Granulocytes are white blood cells derived from the common myeloid progenitor cell. In the granulocytic series, the developmental stages are as follows: hemocytoblast → common myeloid progenitor (or CFU-GEMM) → CFU-GM → CFU-G → myeloblast → promyelocyte → myelocyte → metamyelocyteband cellgranulocyte (particularly, polymorphonuclear leukocytes).
Granulocytes have different cytoplasmic granules as opposed to agranulocytes that seem to lack them. The cytoplasmic granules can be observed through staining technique and light microscopy. Examples of granulocytes are polymorphonuclear leukocytes and mast cells. In humans, the polymorphonuclear leucocytes are subdivided into eosinophils, basophils and neutrophils (according to the staining properties of the granules using a Romanovsky type stain).
The mast cells are considered as a type of granulocyte for having cytoplasmic granules. However, unlike the polymorphonuclear leukocytes derived from the granulocytic lineage, the mast cells arise from the common myeloid progenitor cell without going through the various developmental stages in the granulocytic series.
Hematopoiesis producing granulocytes, particularly polymophonuclear leukocytes, is referred to as granulopoiesis.
Synonym(s):

  • multinuclear leukocyte
  • granular leukocyte

Compare:

  • agranulocyte
  • See also:

    Related term(s):

  • Granulocyte-colony-stimulating factor
  • Receptors granulocyte-colony-stimulating factor
  • Related form(s):

    • granulocytic (adjective, of, pertaining to, or relating to a granulocyte)
    • Granulocytic leukaemia


    You will also like...

    Community Patterns

    Learn about community patterns and the ecological factors influencing these patterns. Revisit some of the ecosystems you..

    Biological Energy
    ATP & ADP – Biological Energy

    ATP is the energy source that is typically used by an organism in its daily activities. The name is based on its structu..

    Control of body movement
    Control of Body Movement

    Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

    Flowers and tiny fruits of the pomegranate plant
    Fruits, Flowers, and Seeds

    This tutorial deals with the structure and function of flowers, fruits, and seeds. Also included here are the types of f..

    New Zealand Flora & Fauna
    Ecology & Biodiversity: New Zealand Flora & Fauna

    New Zealand is known for its unique biodiversity, caused by its remarkable geography and geologic history. Breaking away..

    Fossil trilobite imprint in the sediment
    Insects

    There are more species of insects than any other species combined. This surely illustrates that insects have the selecti..

    Related Articles...

    No related articles found

    See all Related Topics