Identifying white blood cells by morphology

Steps:

• Examine nucleus: round and compact for lymphocytes, kidney-shaped and large for monocytes, multi-lobed for neutrophils.
• Check cytoplasm: scant and clear for lymphocytes, abundant and pale for monocytes, granular for neutrophils.
• Compare sizes: lymphocytes smallest, monocytes largest, neutrophils medium.
• Label X as largest with indented nucleus (monocyte), Y as lobed and granular (neutrophil), Z as small round (lymphocyte).

Why C is correct:

• C aligns with definitions: monocytes have U-shaped nuclei and >15% cell volume cytoplasm, neutrophils show 3-5 nuclear lobes with azurophilic granules, lymphocytes feature near-total nuclear occupation.

Why the others are wrong:

• A: Swaps Y and Z; neutrophils have segmented nuclei, not monocyte-like indentation.
• B: Mislabels Z as monocyte; lymphocytes are too small with minimal cytoplasm for monocytes.
• D: Errs on X as neutrophil; monocytes lack multi-lobing, showing single horseshoe nucleus instead.

Final answer: C