Cellular respiration is a chemical oxidation-reduction reaction that provides the energy needed for a cell to function.C6H12O6 + O2 == CO2 + H2O (+ ATP)
The molecules involved in cellular respiration are:Oxygen O2: from the air we breatheCarbohydrate (glucose): represents a source of energyCarbon dioxide CO2: from glucose degradationATP: the energetic molecules used by the cell
And finally H2O.