Haematopoiesis and the White Cell Flashcards
what are the three types of granulocytes?
neutrophils
eosinophils
basophils
what granulocyte deals with parasites?
eosinophils
what is the function of natural killer cells?
anti viral
anti tumour
what is the lifespan of a RBC?
120 days
what is the lifespan of a neutrophil?
7-8 hours
what is the lifespan of a platelet?
7-10 days
what are the five stages of neutrophil maturation from a myeloblast?
myeloblast promyelocyte metamyelocyte myelocyte neutrophil
what is a ‘blast’?
a primitive nucleated cell precursor
what cell is a platelet precursor?
megakarocyte
are haemopoietic stem cells derived from the endo, ecto or mesoderm?
mesoderm
at what gestation does yolk sac haemopoiesis stop by?
week 10
at what gestation does liver haemopoiesis start at?
week 6
at what gestation does spleen haemopoiesis start at?
week 12
at what gestation does bone marrow haemopoiesis start at?
week 16
where do you take a bone marrow sample from in a child?
tibia
where do you take a bone marrow sample from an adult?
iliac crest
what is the name for the minute projections of bone that are found throughout the metaphysis so that bone marrow is close to the bone surface?
trabeculae
what is the name for the interface of bone and bone marrow?
endosteum
what cells line the endosteum?
osteoblasts, osteoclasts and others
what is the name of specialised venules within the bone that forms a reticular network of blood vessels?
sinusoids
compare red marrow to yellow marrow?
red marrow: active
yellow marrow: fatty and inactive
how do you calculate the marrow cellularity % of a person?
100- age
what happens to the ratio of red to yellow marrow as you age?
ratio decreases
increase in yellow marrow
what is the myeloid:erythroid ratio?
ratio between neutrophils and neutrophil precursors to nucleated red cell precurosors