The various types of White Blood Cells
Given above is a peripheral blood smear at high magnification which shows the various leukocytes forming our immune system. Note that monocytes or macrophages-to-be have a horse-shoe like nucleus while the nucleus of lymphocytes is relatively rounder. Both these cells belong to the group of agranulocytes as their cytoplasm is devoid of big granules which are seen in granulocytes. The granulocytes include basophils, eosinophils and neutrophils named according to the gram staining of their respective granules. Basophils stain deep blue/ purple while eosinophils stain pink. Also note that the basophilic granules often mask the nucleus while neutrophilic nuclei have segments ranging from 3-5. Image via https://www.slideshare.net/meleebirdsong/activity-9bloodheart-60081577