riddle me this - TBR hemoglobin question!

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dukeorhopkinsonly

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Quick question about the effect of temperature on oxygen hemoglobin affinity. The question asks, if the temperature of the blood is increased, which of the following is true:

1. A rise in temperature requires a lower partial pressure of oxygen to bind a given amount of oxygen.

2. A rise in temp requires a greater partial pressure of oxygen to bind a given amount of oxygen.

3. A rise in temperature requires a lower partial pressure of CO2 to bind a given amount of O2.

Obviously because it's a right shift in the curve, it will require a greater partial pressure of oxygen to bind the same amount. But I was under the impression that increasing CO2 would ALSO be a right shift, so my logic was that by decreasing CO2 levels, you would basically have a left shift, and could get back to the same level of oxygen binding.

But the answer says this is not true, and I'm just curious as to why. My thought is that since increased temp lowers Hb affinity for oxygen, decreasing CO2 would increase Hb affinity for O2. Anyone help me out here? Thanks a million!
 
Quick question about the effect of temperature on oxygen hemoglobin affinity. The question asks, if the temperature of the blood is increased, which of the following is true:

1. A rise in temperature requires a lower partial pressure of oxygen to bind a given amount of oxygen.

2. A rise in temp requires a greater partial pressure of oxygen to bind a given amount of oxygen.

3. A rise in temperature requires a lower partial pressure of CO2 to bind a given amount of O2.

Obviously because it's a right shift in the curve, it will require a greater partial pressure of oxygen to bind the same amount. But I was under the impression that increasing CO2 would ALSO be a right shift, so my logic was that by decreasing CO2 levels, you would basically have a left shift, and could get back to the same level of oxygen binding.

But the answer says this is not true, and I'm just curious as to why. My thought is that since increased temp lowers Hb affinity for oxygen, decreasing CO2 would increase Hb affinity for O2. Anyone help me out here? Thanks a million!
can you elaborate more? i isually use this figure for T effects on Hb (from wikipedia)


Oxyhaemoglobin_dissociation_curve.png
 
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