Solution :
The flow of oxygen in the blood is been transported by two ways :
1. in plasma 1.5%
2. bound to hemoglobin 98.5%
As the oxygen loads in the body, affinity of the Hb makes the oxygen loading very efficient in the blood. The Hb molecule gets saturated when all the 4 hemes are oxygen binded.
The decreased pH weakens the hemoglobin oxygen binding in the tissues.
Higher temperatures in the oxygen means a lower affinity and thus more oxygen is released and so the oxygen unloads.
Increase in the temperature, the BPG and the modification of the structure in the hemoglobin decreases the affinity for the oxygen and further enhances the unloading of the oxygen in the blood.