The greatest amount of CO2 transported in blood is in the form of bicarbonate in plasma. Most of the carbon dioxide is converted into bicarbonate with the help of carbonic anhydrase which is an enzyme. This enzyme converts carborn dioxide and water into bicarbonate and hydrogen ions. The bicarbonate in plasma accounts for about 70% of CO2.
Yeah it uses some valuable scientific vocabulary and background knowledge, I hope this hypothesis will be good enough for your teacher (don't worry it will be)
