What are erythroid series?

RETICULOCYTE - juvenile red cells devoid of nuclei but contain ribosomal RNA so that they are still able to synthesise haemoglobin. Normal range :- Adults - 0.5-2.5% Infants - 2-6% Increased in - haemorrhage, haemolysis and haematopoietic response of anaemia to treatment RED BLOOD CELLS - non-nucleated cells, biconcave disc, 7.2 μm in diameter, and has a thickness of 2.4 μm at the periphery and 1 μm in the centre. The lifespan of red cells is 120 +/- 30 days.