In the bohr effect why is it when co2 concentrations are high the haemoglobin affinity for 02 is decreased?

Question

any help will be appreciated

Answer 1

i think its because haemoglobin always has a higher affinity for co2. When its in higher concentrations, o2 is reduced by heaps because co2 requirees less energy to be bonded to haemoglobin.. something like that.

hope this helpz

Answer 2

If we were to design an oxygen delivery system, we would like to deliver more oxygen to the more active tissues, the ones that need the oxygen. How would we know if a tissue is more active and requires more oxygen? One way is by the amount of oxygen present in a tissue. If the tissue is using more oxygen, then one would expect the amount of oxygen (pO2) would be lower.

Another indicator that a tissue has a high metabolic rate (and thus a need for increased oxygen delivery) is the production of carbon dioxide. When a tissue is more active, the amount of carbon dioxide produced will be increased (pCO2 is higher). Carbon dioxide reacts with water as shown in the following equation:

CO2+ H2O <---------> H+ + HCO-3

What this means is that as the amount of carbon dioxide increases, more H+ are formed and the pH will decrease. Thus, a lower pH in the blood is suggestive of an increased carbon dioxide concentration which in turn is suggestive of a more active tissue that requires more oxygen. According to Bohr, the lower pH will cause Hb to deliver more oxygen! Just what you and I want to occur. Right!