Lecture 1: Normal haematopoiesis Flashcards
What is haematopoiesis?
The formation of blood
Where does haematopoiesis occur in embryos, infants and adults?
Embryos- yolk sac, liver & spleen then bone marrow. Infants- Bone marrow of all bones. Adults- bone marrow of central bones e.g. sternum and pelvis and ends of femur bones
What are the two progenitor cells of lymphocytes and other blood cells?
Common myloid progenitor differentiates into all blood cell types except B and T cells which come from common lymphoid progenitors.
What do megakaryocytes produce?
Plasma cells for blood clotting
What controls haematopoiesis?
Extrinsic factors such as growth factors and intrinsic factors such as transcription factors
Give some examples of growth factors which control erythropoiesis.
Erythropoietin- controls RBC production (stimulated by low oxygen levels). G-CSF- a neutrophil growth factor. Thrombopoietin- platelet growth factor.
What is fluctuations are considered normal in a full blood count?
The mean + or - 2 standard deviations
what is a reticulocyte?
An immature red blood cell
What do the endings -cytosis and -cytopenia mean?
-cytosis= too much, -cytopenia= too little
What can be the cause of cytopenia?
Either not enough production or loss after production
What is leucopaenia?
Too few white blood cells, especially neutrophils.
What is thrombocytopenia?
Too few platelets resulting in bruising and gum an nose bleeding.
What is the reticuloendothelial system?
The removal and recycling of old red blood cells by the spleen
What are possible causes of anaemia?
Reduced RBC production, iron deficiency, B12 deficiency, autoimmunity, RBC destruction
What do iron deficient red cells look like?
Not as much colour in the middle
