● Yolk sac → liver → spleen → bone marrow through life stages foetus → infancy →
childhood
● Erythropoiesis: Stem cell → CFUGEMM → BFUE → CFUE → proerythroblast →
erythroblast/nucleated RBC → reticulocyte → mature RBC
○ 1 proerythroblast = 16 RBC
○ Erythropoietin production from kidneys stimulated from hypoxia/ low O2 tension through
HIF-2α and HIF-β
○ EP increases:
■ number of progenitor cells committed to erythropoiesis
■ Differentiation rate of BFUE and CFUE
■ Activation of erythroid specific genes eg haem, RBC membrane
■ Expansion into fatty marrow and extramedullary sites if chronic hypoxia
● Leukopoiesis can either be myeloid or lymphoid.
○ Myeloid: Stem cell → CFUGEMM → CFUGEMEo → CFUGM → CFU-M or CFU-G →
monocyte or neutrophil
○ Lymphoid: stem cell → common lymphoid progenitor cell → B/T
lymphocytes or NK cell
○ Granulocyte-macrophage colony-stimulating factor (GM-CSF) are growth factors for all
leukocytes cells. Granulocyte colony-stimulating factor (G-CSF) for granulocytes
○ Growth factors are stimulated by already present leukocytes secreting interleukins
● Thrombopoiesis: Stem cell → CFUGEMM → CFUEMK → CFUMK → megakaryocyte →
platelets
○ Thrombopoietin released from liver is stimulated by Tpo
○ TP enables megakaryocyte cell growth → platelets and stimulates platelet
activation during coagulation
○ Platelets created from megakaryocyte cytoplasm from pseudopodial projections which
break off. Exact maturation mechanisms afterwards are unknown, but microtubules are
stimulated to deliver intracellular components to platelet fragments
○ 1 megakaryocyte = 1500-4000 platelets
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller kayrose. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $0.00. You're not tied to anything after your purchase.