The bohr effect

Haemoglobin becomes almost fully staurated with oxygen at high oxygen concentrations such as in the lungs. 

Oxyhaemoglobin dissociates under low oxygen concentrations such as in respiring tissues which are using up oxygen. 

* the curve is s shape because after the first oxygen molecule has joined to one of the 4 haem groups, the haemoglobin molecule becomes distorted, making it easier for the other ones to bind to other haem groups. 

*At higher co2 concentrations, the oxygen dissocociation curve moves to the right. Higher concentrations of co2 increase the dissociation of oxyhaemoglobin. 

outline how this effect ensures more efficient delivery of oxygen to tissues when exercising

exercise produces a higher concentration of carbon dioxide in the tissues. 

respiration> glucose +oxygen +o2 > co2+h2o +energy

the haemoglobin unload and gives out oxygen more readily.