Reticulocyte

3D Model

Reticulocytes are the precursors to erythrocytes, they have expelled the nucleus that existed in the erythroblast, an earlier stage in the development of red blood cells. Unlike erythrocytes, they still contain messenger RNA and the machinery to make proteins, although these will be lost as they complete their differentiation. They are slightly larger and darker coloured than erythrocytes and are undergoing the shape change into a disc, like the reverse of crumpling up a paper ball.