Erythroid series

The erythroid series of cells, also known as erythropoiesis, is the process of producing red blood cells in the bone marrow. The erythroid series of cells includes the following stages:

Proerythroblast: This is the earliest stage of red blood cell development, and it is characterized by the presence of a large nucleus and a small amount of cytoplasm.

Basophilic erythroblast: At this stage, the red blood cell precursor begins to synthesize hemoglobin, which gives it a blue color when stained.

Polychromatophilic erythroblast: At this stage, the red blood cell precursor has increased its hemoglobin synthesis and begins to lose its blue color, becoming more pink or purple.

Orthochromatic erythroblast: This stage is characterized by the complete synthesis of hemoglobin and the expulsion of the nucleus. The cell is now a reticulocyte.

Reticulocyte: This is the final stage of red blood cell development before it becomes a mature erythrocyte (red blood cell). Reticulocytes still contain some residual ribosomal RNA, giving them a "reticular" or network-like appearance when viewed under a microscope.

Erythrocyte: This is the fully mature red blood cell, which is biconcave in shape and lacks a nucleus. It is responsible for carrying oxygen from the lungs to the body's tissues.