Haemopoiesis Flashcards
What is haemopoiesis?
Formation of blood cells
What is erythropoiesis?
Formation of red blood cells
What is thrombopoiesis?
Formation of platelets
What is myelopoiesis/granulopoiesis?
Formation of granulocytes
What is lymphopoiesis?
Formation of lymphocytes
What is cell production like in the steady state?
Cell loss is balanced by cell production
What cell type would decrease first if haemopoiesis is switched off rapidly?
Neutrophils
What are the steps in red cell production?
Pronormoblast - early normoblast - intermediate normoblast - late normoblast - reticulocyte - erythrocyte
What is the ancestry of neutrophils?
Myeloblast - promyelocyte - myelocyte - metamyelocyte - band neutrophil - neutrophil
What is the progenitor cell of platelets?
Megakaryocytes
What do precursor cells develop from?
Mononuclear haemopoietic progenitor cells produced by haemopoietic stem cells
What can mutlipotent progenitors give rise to?
Both myeloid (non-lymphoid) and lymphoid progeny
What ability to stem cells have that is unique to them?
Ability to self-renew = this ability is lost as they differentiate and mature
What state are most primitive progenitors (e.g stem cells) in during steady state haemopoiesis?
They are dormant
Where do stem cells originate from embryologically?
The mesoderm
How early in development are circulating committed progenitors detectable?
As early as week 5
Where is the first site of erythroid activity during development?
The yolk sac = stops by week 10
Liver starts by week 6 and bone marrow by week 10