mod 3- RBCs Flashcards
(16 cards)
what is the key element in heme and what does it bind
Iron can bind 6 things (4N and 2 O2)
what are the 2 states that Hb can exsist in
Tense- low affinity for O2
Relaxed- High affinity for O2
how does each bind of O2 change the state
as it binds more it moves closer to the relaxed state
How does C02 affect binding of O2
binds 200x better
-co2 bound to fe blocks o2 from binding at the lungs
what are the 3 factors that increase release of O2 from hb @ tissues
- hydrogen ions
- covelent binding of co2
- 2-3 BPG
How does hydrogen ions affect binding
Co2 is converted to carbonic acid in RBC
Carbonic acid difusses in bicarbonate + hydrogen which lowers PH
H competes w ox causing ox to be less sat
how does covelent binding of Co2 affect binding
directly competes w ox
how does 2-3 bpg affect binding
found in equal parts to hemeglobin in RBC and it increases the amount of o2 released
at altitude body makes more BPG
steps of iron absorbtion in body
- absorbed in ferrous form
- fe2->fe3 so it can be absorbed (done by feroxidase)
- Transferin binds to iron to allow it to travel
where is iron absorbed and percentages
75%- bone marror
20% to liver
5%- other tissues
anemia vs hemochonmatisis
anemia- iron lost in menstration
hemochonatosis- inability to excrete iron
What is the erythrocyte skeleten and what is the most important component
gives protection and shape
- most important component is spectrin
where is RBCs formed and from what
Pluripotent stem cells in bone marrow
What stims RBC maturation
Erythropotin from kidneys
how is hemoglobin different in infants
in infants 2-3 bpg doesnt bind as well so ox will bind tighter so it can get to the infnts tissues
What typeof RBS in:
- impaired hemo synthesis
- impaired dna synthesis
- RBC loss
- microcytic (iron def.)
- macrocytic (vit b12)
- Normocytic (acute bleeding)
