And so the carbon dioxide cannot actually be stored inside the cytoplasm of the red blood cells in its CO2 form. And so what ultimately has to happen is the cell has to carry out this particular reaction in which we transform the non polar CO2 molecule into its polar form, bicarbonate ion. And because this contains a full negative charge, it can easily dissolve inside the cytoplasm of the red blood cell and also inside the blood plasma of our body. So the problem with this reaction is so if we study the rate of this reaction in its uncatalyzed form at a PH of seven, at body temperature of, let's say, 37 degrees Celsius, we'll see that the rate of the reaction isn't that great. In fact, the rate is nowhere close to what it should be to actually be able to meet the demands of all the trillions of metabolizing cells found inside our body. So to basically increase the rate to a high enough value so that it can keep up with the demands of our body, what the red blood cells have is they have this enzyme we call carbonic anhydrase, too.