Objective 64: How oxygen and carbon dioxide is transported

These videos helped me to understand both oxygen and carbon dioxide transport through the body.  I remember having a discussion in lab about this topic and at first I thought I knew it all but then there was talk about bicarbonate.  What I learned is that carbon dioxide produced in the tissue cells diffuses into the blood plasma. The largest fraction of carbon dioxide diffuses into the red blood cells. The carbon dioxide in the red blood cells is transported as: dissolved CO2, combined with hemoglobin, or as bicarbonate.  Bicarbonate
diffuses out of the red blood cels into the plasma in venous bood and visa versa in arterial blood. Chloride ion always diffuses in an opposite direction of bicarbonate ion in order to maintain a charge balance. This is referred to as the "chloride shift".
In the lungs, oxygen diffuses from alveolar air into the blood because the venous blood has a lower partial pressure. The oxygen dissolves in the blood.