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22 Cards in this Set
- Front
- Back
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What is the point of Heme?
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heme basically bonds O2 to the hemoglobin
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Heme is a complex of what 2 things
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Heme is a complex of protoporphyrin IX and the ferrous Iron Fe2+
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How many bonds can the Fe2+ have?
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it can have 6, 4 of which are bound to O2.
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What is the nonfunctional form of Fe+2 ? Why do you get it?
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It is Ferric form Fe3+. You get this form of iron without the protein portion of the molecule.
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What kind of amino acids do you find on the inside of a hemoglobin protein?
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they would hydrophobic so Ile, Leu, Val etc
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What is the point of AA F8?
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it binds to the 5th cordination of the heme iron.
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What is the point of AA E7
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it helps O2 to bind to the 6th coordination and inhibits CO binding
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How does E7 prevents CO to bind well to the molecule
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basically it is a steric hinderance forcing CO to bind at an angle which makes this not very favorable. O2 likes to bind at angle so it can stick better to the molecule than CO
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Which chromosome is the alpha genes located; the beta ones?
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alpha - 16;
beta - 11 |
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What are the 2 forms of Hb in the already assembled state. ie not alpha 2 beta 2. maybe called the activated form
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they would be the tense and the relaxed. the tense forms ionic and hydrogen bonds which makes it difficult for the o2 to bind. the relaxed form by the virtual of an o2 bindinng to these bonds found in the tense form are broken faciltating other 02 to bind to the molecule. Thei is cooperative binding
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Which binds o2 stronger, Myoglobin or Hb
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Myoglobin.
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What is p50? What is the p50 for Myoglobin? for Hb?
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p50 is the partial pressure required to achieve half-saturation of the binding sites. for Myoglobin is it 1 for HB it is 26.
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What does a lower p50 value mean?
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it means a higher oxygen affinity
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Why is the oxygen affinity curve for Hb sigmoidal?>
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as mentioned before it is because the o2 binding is cooperative. it is hard for the first one to bind but after that first molecule binds then others can bind again. the same is true for unloading. once one o2 is unloaded the other unload easier
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What happens in Hemoglobin H diesase and Hydrop
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basically you get a deletion of the alpha gense so you get HbH Beta 4 and Hb Bart's and you get not get cooperative binding
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What happens when you get lots of CO2 and H+; What happens to the O2 affinity curve? When do you see these condition?
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Basically it lowers the O2 affinity to Hb. this shifts the curve to the righ. Also higher levels of of C02 and H+ change the quaternary structure promoting the release of O2 from oxyhemoglobin
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What does carbonic anhydrase do?
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This converts CO2 to carbonic acid
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What do H+ ions do to the Hb
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It stabilizes the the deoxy form of hemoglobin by binding to the N-terminal of alpha amino groups and other histidine. CO2 does basically the same thing. stabilizes the molecule. so it lowers its affinity to oxygen.
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What does 2,3-BPG do to Hb
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it lowers the affinity of Hb by binding to the deoxyHb and stablizing this form. This also facilitaes the release of O2
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When do you find lots of 2,3 BPG
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in chronic hypoxia and high altitudes and in chronic anemia
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What kinds of Hb do you find in adults?
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alpha and beta mostly with some alpha and delta
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what kinds of Hb do you find in fetal Hb?
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alpha 2 and gamma 2
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