Anaemia: Histology Flashcards
three broad types of blood cells
- red blood cells
- white blood cells
- platelets
what is the production of blood cells called?
haematopoiesis
what are blood cells derived from?
pluripotent stem cells
sites of haematopoiesis in the embryo
yolk sac > liver > marrow > 3rd-7th month spleen
sites of haematopoiesis at birth
bone marrow, then liver and spleen when needed
sites of haematopoiesis in adults
axial skeleton bone marrow (skull, vertebra, ribs, sternum, pelvis, proximal femur)
neutrophil development pathway
myeloblast promyelocyte myelocyte metamyelocyte neutrophil
nucleus gets smaller and darker as cycle continues
erythropoiesis cells in cycle
pronormoblast basophilic/ early normoblast polychromatophilic/ intermediate normoblast orthrochromatic/late normoblast reticulocyte erythrocyte
cell size reduces throughout this cycle
platelet development
buds from cytoplasm of megakaryocytes
what are the three types of granulocytes?
- eosinophils
- basophils
- neutrophils
what do eosinophils look like?
pink/orange stain
bilobed nucleus
function of eosinophils
fight parasites
hypersensitivity reactions
what do basophils look like?
large purple/ blue granules that obscure the nucleus
infrequent
role of basophils
unknown
circulatory version of mast cells so hypersensitivity, GcReceptor binds IgE and granules contain histamine
what do neutrophils look like?
polymorph nucleus with neutral staining