(rĕ-tik'yŭ-lō-sīt‵ )

[reticulo-+ -cytel]

The last immature stage of a red blood cell. Its darkly staining granules are fragments of the endoplasmic reticulum. Reticulocytes normally constitute about 1% of the circulating red blood cells. Reticulocyte counts increase as a normal response to anemia.