erythrocyte production and descruction

Main functions of RBCs

Deliver oxygen from lungs to tissues, carry carbon dioxide from the tissues back to the lungs, buffer blood pH

Getting rid of excess CO2 buffers the pH

maturation of RBCs in order

BFU-E —> CFU-E—> Pronormoblast —> basophilic normoblast —> polychromatic normoblast —> orthochromic normoblast —> reticulocyte (polychromatic erythrocyte) —> erythrocyte

Factors that determine stage of maturation of blood cell

Determined by nucleus and cytoplasm characteristics

Nuclear chromatin pattern, nuclear diameter, nucleus:cytoplasm ratio, presence or absence of nucleoli, cytoplasmic color

What are the appearance trends as RBCs mature?

1: overall diameter of cell decreases

2: nucleus:cytoplasm ratio decreases

3: nuclear chromatin pattern gets coarser, clumped and condensed

4: nucleoli disappear

5: cytoplasm changes from blue to gray-blue to salmon-pink

Pyknotic

Nucleus eventually loses all parachromatin (light to white staining appearance) and becomes extremely condensed