Which feature describes the structure of a monocyte/macrophage?

Which feature describes the structure of a monocyte/macrophage?

• A. Fine cytoplasmic granules
• B. Large, horseshoe-shaped nuclei
• C. Small round nuclei
• D. Segmented nuclei

Answer: (B)

Monocytes/macrophages are distinguished by a single, large nucleus that is horseshoe-shaped (often described as kidney-shaped). This prominent, indented nucleus stands out against their abundant cytoplasm and large cell size, setting them apart from other white blood cells. Lymphocytes have a small, densely staining round nucleus; neutrophils show a multi-lobed, segmented nucleus; eosinophils and basophils have other distinctive features. The horseshoe-shaped nucleus reflects the mononuclear phagocyte lineage and helps explain why these cells function as circulating precursors that become macrophages in tissues.

Monocytes/macrophages are distinguished by a single, large nucleus that is horseshoe-shaped (often described as kidney-shaped). This prominent, indented nucleus stands out against their abundant cytoplasm and large cell size, setting them apart from other white blood cells. Lymphocytes have a small, densely staining round nucleus; neutrophils show a multi-lobed, segmented nucleus; eosinophils and basophils have other distinctive features. The horseshoe-shaped nucleus reflects the mononuclear phagocyte lineage and helps explain why these cells function as circulating precursors that become macrophages in tissues.