Assignment task: Describe and discuss the role (or the significance) of CO2 in the body.
You may choose to discuss CO2 in the context of respiration. You may wish to discuss the role of CO2 in stimulating breathing or in the body's acid-base balance and blood buffer system. You should explain how CO2 is produced by the body and eliminated from the body.
Your essay should contain some physiology, and (where appropriate) some physical science and chemistry (eg how CO2 is transported in the blood and the role of carbonic anhydrase).
You could include (among other things) appropriate discussions about the effect of having too much CO2 dissolved in the body.