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12 Cards in this Set
- Front
- Back
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How is the Red Cell Membrane composed?
what is the most important protein, why? |
it is a lipid sandwich with a matrix of proteins, of which SPECTRIN is most important - it provides flexibility.
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what is the RBC lifespan?
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120 days
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why does the RBC require flexibility?
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passes through spaces less than 3 micra in circulation, less than 0.5 micra in the spleen!
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What four factors play a role in RBC membrane deformability?
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-Membrane deformability
-Cell SA:Vol ratio -Cytoplasmic viscosity -Age-dependent changes |
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how does cytoplasmic viscosity affect deformability?
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the more viscous, the harder the cell is.
sickled cells are crystallized cytoplasm and jam in the spleen |
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What are 7 decreases, 6 Increases with age that cause flexibility to decrease in RBCs?
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Decreased: enzyme, K, Phospholipid, water, ATP cholesterol, MCV.
Increased: Na, cell viscosity, met-HgB, MCHC, O2 affinity, memb. bound IgG |
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What is RBC catabolism?
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the breakdown of hemoglobin into its cellular elements
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what are the 2 types of RBC catabolism?
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-Extracellular
-Intracellular |
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Which is more, extra or intravascular catabolism? How much?
Where is extra? Where is intra? |
Extra - 90%. takes place in SPLEEN
Intracellular - 10%, takes place in liver after RBC ruptures in circulation |
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what are the 5 organs of the RES?
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spleen
liver lymph nodes b marrow monocytes |
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what are the 5 types of cells that constitue the RES?
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fixed macroph
free macroph endothelial cells lining sinusoids fibroblasts circulating monocytes in blood |
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what are the 5 components of the spleen that make it great for RBC catabolism?
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1. lymphatics - allow for self/nonself recognition.
2. Old folks home - slow/stagnate allows cells to stay a while and get fixed 3. Beauty salon - Ig get picked off, fix damaged membrane, remove inclusions 4. Nursery - retics/polychr. large cells get stuck and mature for a while. 5. Storage site - 20-30% RBCs, platelets |
