Haemopoiesis Flashcards
What is haemopoiesis?
the formation of blood cells
what is proliferation?
the expansion of a cell line
what is differentiation?
the variation of a cell line
what does a pluripotent stem cell differentiate into?
myeloid lineage or lymphoid lineage
what are the myeloid cells?
erythrocytes, granulocytes, monocytes and platelets
what are the lymphoid cells?
t and b lymphocytes
can progenitor cells be microscopically visualized?
no, only when grown in culture
what are progenitor cells also known as?
colony forming units
where are pluripotent and progenitor cells found?
bone marrow
where does foetal haemopoiesis occur?
bone marrow, liver, lymph nodes and spleen
where does embryonic haemopoiesis occur?
in the yolk sac
what is the area vasculosa?
part of the yolk sac where blood vessels are found
what is intramedullary haemopoiesis?
haemopoiesis occurring in the bone marrow
what is extramedullary haemopoiesis?
haemopoiesis occurring outside of the bone marrow
what are the phases of haemopoiesis?
- mesoblastic/embryonic
- hepatosplenic
- myeloid/bone marrow
when does the mesoblastic phase of haemopoiesis occur?
first few weeks to two months of gestation
what are the types of primitive haemoglobin?
Gower and Portland
what type of cells are produced by primitive haemopoiesis?
mainly erythrocytes
where does the hepatosplenic phase of haemopoiesis occur?
mainlyin liver but also in spleen
when does hepatosplenic haemopoiesis occur?
2-7 months, max 4
what is the main type of Hb produced in the hepatosplenic phase?
Hb F
when does the myeloid phase occur?
5-9 months and continues throughout life
what does Hb A consist of?
4 haem molecules attached to 4 globin chains (2a and 2B)
where does adult haemopoiesis take place?
red marrow of the bone marrow
- femur, cranium, hips, pelvis, spine, ribs, sternum
what does yellow marrow act as?
a fat store
what regulates blood cell production?
growth factor hormones
environmental factors
oxygen levels
cytokines
