week 1 Flashcards
life span of a red blood cell?
120 days
mitochondira?
no
do they contain DNA?
no
how are rbcs removed from circulation?
phagocytic cells of liver and spleen engulf them
formed from ?
pluripotent stem cells
ahem broken down into?
bilirubin(which colours urine and faeces)
what released by kidney into ciculation which stimulates erythropoesis?
EPO
what keeps iron in fe2+ state?
NADH from glycolysis
glubuar haemoglobin broken down into?
amino acids which enter the blood stream
what does iron bind to in the blood before it is recycled?
transferrin
biconcave disk - 8um diameter, 2um thick at edge, 1um thick in centre
plasme = 55% of whole blood
buffy coat consists of?
platelets and white blood cells
male 4.5-6.5 x10 12/litre blood
female 3.8-5.8
rbc ion balance and cell volume are actively regulated by energy dependant naKATPases (the sodium pump)
rbcs have no mitochondria, therefore anaerobic glycolysis is the only route for ATP synthesis
y
what keeps iron in the fe2+ state?
NADH from glycolysis
what is HbFe3+?
metaemoglobin - it can’t bind 02
some glucose is metabolised through the hexose monophosphate shunt
this produces NADPH, which is required for the maintenance of adequate levels reduced gltathione
when is 2,3 bpg produced?
when po2 is reduced, 23 bp releases oxygen from Hb
3 peptides in glutathione?
glutamate, cysteine and glycine
what are free radical?
highly reactive molecules with unpaired electrons
excessive free radicals or lack of anti oxidants lead to?
damage of cellular structures and ennzymes
glutathione helps protect against toxic effects of reactive oxygen species
reduced glutathione is essential to detoxify hydrogen peroxide
what is needed from the pentose phosphate pathway to produce reduced glutathione?
NADPH
enzyme that catalyses hydrogen peroxide into 2 water?
glutathione peroxidase
3 ways c02 is transported to the lungs?
dissolved in plasma (10%), bound to hb as cardamon haemoglobin (30) and as bicarbonate ion 30%
facilitated by?
carbonic anhydrase
how does bicarbonate enter lung cell?
chloride bicarbonate exchange by facilitated diffusion
what is H+ buffered by?
deoxygenated Hb (forms HHb)
HC)3 imported, cell shrinks, cl enters cell swells
reaction is driven backwards to blow off CO2
4 globin molecules, 4 haem groups, 4 fe ions
ahem group = porphyrin ring
fetal - a2y2
adult a2b2
normal haemoglobin concentrations? (male and female?)
male 130-180
female 115-165
