L13- red cell production Flashcards
(27 cards)
rbc formation
day 1- proerythroblast - produced frpm multipotential myeloid stems under influence of erythropoietin
day 2- basophylic erythroblast - smaller than proerythroblsdt, more ribosomes which produce haemoglobin
day 3- polychromatophilic erythroblast- last precursor- capable of mitosis- smaller than basophiilic erythroblast
day 4- normoblast- incapable of cell division- nucleus is ejected
day 5-7- reticulocyte- some ribosomes and has a slight basopbilic stain
erythrocyte- released from bone marrow into circulation
where do rbc formation stop after 20 years
femur and tibia
2 million cells produced per
second
blood composition
92% water
7% plasma proteins - albumin globulin fibrinogen
1% other solutes- electrolytes nutrients and wastes
do rbcs proliferate
no
what happens after 120 days
10% rupture, 90% engulfed by phagocytes
large numbers of rbc rupturing effect on urine
urine turns red/brown
haematuria
presence of intact rbc in urine
how is biliruben transported from blood to liver
albumins
increased bilirubin in blood
diffuses into tissues and turns them yellow - jaundice
iron from haem
stored in phagocyte or released into blood , blood iron binds transferrin and transports it to bone marrow, liver and spleen for reuse
erythrocyte
membrane has -ve surface charge
membrane is a lipid bilayer with outerglycoprotein coat
inner protein molecules form a filamentous cytoskeleton of spectral, actin and ankyrin
energy metabolism for RBC
energy needed to maintain iron and NAK conc
glucose reuptake via GLUT 1 transporter
anaerobic resporation
pentose phosphate pathway
control of plasma volume and RBC mass
via kidneys
hematocrit
volume percentae of red blood cells in blood to packed cell volume , a measure of capability of oxygen delivery
men vs women hematocrit
40.7-50.3% men
36.1-44.3% women
decreased oxygen supply stimulates
erythropoietin secretion from kidney cells - which rbc production
epo stimulates
proliferation and differentiation of progenitor stem cells to produce mature RBC
factors affecting RBC production
iron- role in haemoglobin structure
vitamin b12 and folic acid- essential for final maturation of rbc
vitamin C - reduce ferric form of iron to ferrous to facilitate absorption and transport
anaemia
decrease in haemoglobin or RBC, decreasing ability to transport ocygen to tissue cells, causin blood loss
acute blood loss
haemorrhage
chronic blood loss
menorrhagia
universal recipient
AB
