Quick Review Cards for Medical Laboratory Science

Erythrocytic Developmental Series Hematology Review 295

RUBRIBLAST TERMINOLOGY NORMOBLAST TERMINOLOGY KEY CHARACTERISTICS

Rubriblast

Prorubricyte

Rubricyte

Metarubricyte

Reticulocyte

Mature erythrocyte

Pronormoblast

Basophilic normoblast

Polychromatophilic normoblast

Orthochromic normoblast

Polychromatophilic erythrocyte

Mature erythrocyte

14–24 m. N:C ratio 8:1. Royal blue cytoplasm. Fine chromatin.

1–2 nucleoli. Normally confined to bone marrow.

12–17 m. N:C ratio 6:1. Chromatin is coarser with slightly

visible parachromatin. Nucleoli usually not visible. Normally

confined to bone marrow.

10–15 m. N:C ratio 4:1. Cytoplasm is polychromatophilic due

to hemoglobin production. Chromatin is clumped with distinct

areas of parachromatin. Last stage to divide. Normally confined

to bone marrow.

8–12 m. N:C ratio 1:2. Nucleus is pyknotic. Last nucleated stage.

Normally confined to bone marrow.

7–10 m. No nucleus. Cytoplasm is diffusely basophilic (bluish

tinge). Reticulum seen with supravital stain. 0.5%–1.5% of

RBCs in adult peripheral blood.

7–8 m. Biconcave disk. Reddish-pink cytoplasm with area of

central pallor 1/3 diameter of cell.