= Granulocyte
A \b[granulocyte] is a <leukocyte> characterized by abundant cytoplasmic granules. The major circulating categories include <neutrophils>, <eosinophils> and <basophils>. The term groups cells by characteristic morphology and related biology; it does not mean that every granule has the same contents or that every <granulocyte> performs the same immune function.https://www.ncbi.nlm.nih.gov/mesh?term=Granulocytes[NLM Granulocytes scope note and child categories]{ref}
For a simple classification example, imagine a differential count of 100 <leukocytes> containing 60 <neutrophils>,3 <eosinophils> and 1 <basophil>. The total is 64 <granulocytes>, not 60, even though <neutrophils> are the largest component in this invented sample. The example separates a broad category from its most numerous member; it is not a reference interval for a patient.
Morphology also should not be substituted for a functional measurement. <S. D. Wright> and <S. C. Silverstein> measured <hydrogen peroxide> release when human <granulocytes> and other <phagocytes> spread on surfaces bearing different recognition molecules. Surfaces coated with <IgG> produced a strong oxidant response, whereas <C3b>- or <iC3b>-coated surfaces did not produce appreciable peroxide release under the tested conditions.<Receptors for C3b and C3bi promote phagocytosis but not the release of toxic oxygen from human phagocytes by S. D. Wright and S. C. Silverstein>[Abstract: granulocytes, ligand-coated surfaces and peroxide measurements.]{ref}
Thus the presence of granules or a capacity for <phagocytosis> does not by itself establish which signaling pathway was activated. Cell identity, receptor stimulation, uptake and extracellular release are different experimental variables.
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