In order for the exchange of oxygen and carbon dioxide to occur, both gases must be transported between the external and internal respiration sites. The function of respiration is to provide oxygen for use by body cells during cellular respiration and to eliminate carbon dioxide, a waste product of cellular respiration, from the body. The other major activity in the lungs is the process of respiration, the process of gas exchange. Describe the carbonic acid – bicarbonate buffer system.Describe the changes in the composition of the blood that occur with the onset of neonatal life.By the end of this section, you will be able to: