According to Bohr's effect, the affinity of oxygen with haemoglobin depends on the pH of blood. As the concentration of carbon dioxide is less near alveoli or lungs the haemoglobin binds with oxygen on higher rate as the pH of blood is on higher side it reaches towards tissue the concentration starts to increase and pH decreases its affinity towards oxygen also decreases. It was given by Christian Bohr in 1904.
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