What are the different types of WBC?

Lecocytes are WBC. These are colourless, large, nucleated. This is classifies in to two groups: (A) Granulocytes (B) Agranulocytes.

(A) Granulocytes:

Leukocytes characterised by the presence of differently staining granules in their cytoplasm when viewed under light microscopy. These are of 3 types.

i) Neutrophil: Many lobed nucleus , killed foreign bacteria.

ii) Basophil: The nucleus is bi- or tri-lobed, but it is hard to see because of the number of coarse granules which hide it. They are characterized by their large blue granules.

iii) Eosinophil: Generally their nucleus is bi-lobed. The cytoplasm is full of granules which assume a characteristic pink-orange color with eosin stain.

(B) Aganulocytes:

Leukocytes characterized by the apparent absence of granules in their cytoplasm. These are of two type.

i) Lymphocytes: Lymphocytes are much more common in the lymphatic system. Lymphocytes are distinguished by having a deeply staining nucleus which may be eccentric in location, and a relatively small amount of cytoplasm.

ii) Monocyte: Monocytes eventually leave the bloodstream to become tissue macrophages which remove dead cell debris as well as attacking microorganisms.