Which cell is described as a central rounded area of hemoglobin surrounded by a clear zone, with a dense ring of hemoglobin around the periphery?

• A. Plasma cell
• B. Target cell
• C. Spherocyte
• D. Reticulocyte

Answer: (B)

This question is about recognizing the target cell pattern on a blood smear. The described appearance—central rounded area of hemoglobin, a surrounding clear zone, and a dense ring of hemoglobin at the edge—is the hallmark of a target cell (codocyte). It happens when the red cell has more membrane surface area relative to its hemoglobin content, causing the hemoglobin to pull to the rim while a pale center remains. This produces the characteristic bullseye look seen in conditions that alter the cell membrane or Hb content, such as certain hemoglobinopathies and liver disease.

A plasma cell is a mature immune cell and doesn’t relate to red cell morphology. A spherocyte is a small, round red cell lacking central pallor, not showing the central clear zone and peripheral ring pattern. A reticulocyte is an immature red cell with residual RNA that often appears bluish and polychromatic and does not exhibit the target “bullseye” appearance.