76. erythtropoesis

Question 1

What is it and how is it stimulated

Answer 1

produces RBCs.
stimulated when there is a decreased O2 which is detected by the kidneys + secrete hormone erythropoietin

Question 2

what happens to the cells during erythropoiesis

Answer 2

Cell and nuclear volumes decrease,
Nucleoli diminish in size and disappear.
Chromatin density increases
Decrease polyribosomes (basophilia),
increase in the amount of haemoglobin (a highly eosinophilic protein).
Mitochondria / other organelles gradually disappear

Question 3

what does erythropoietin do

Answer 3

stimulates production of RNA for haemoglobin and rbc produtcion

Question 4

what are the maturation stages

Answer 4

1. hemocytoblast becomes myoloid progenitor or multipotent stem cell.
2. unipotent stem cell then pronormoblast
   3.early normoblast
3. intermediate normoblast
4. reticulocyte
   cell is then released and new rbc hv 1% reticulocytes. They lose all polyribosomes, and mature as erythrocytes.