AQA BIOL2~3rd June 2013~AS Biology (Now Closed) Watch
loading = high pp of oxygen and low pp of co2
unloading = low pp of oxygen and high pp of co2
Mainly the partial pressure of oxygen. BUT, presence of CO2 causes the haemoglobin molecule to change shape and so it has a lower affinity for oxygen and releases oxygen more readily into the cells. So there are two things to mention. When talking about loading oxygen in the lungs, talk about the partial pressure of O2. If respiration is involved, talk about CO2.