Cellular respiration consists of several chemical reactions that start with glucose and that follow two pathways, one for aerobic respiration that takes place in the presence of oxygen and the other for anaerobic respiration that takes place in the absence of oxygen.
The final product in both cases is adenosine triphosphate (ATP) that is the energy carrier produced and waste material. Aerobic respiration is a very efficient process that produces 29-30 ATP per molecule of glucose though ideally the output should be 38 ATP. Anaerobic respiration on the other hand produces only 2 ATP for each molecule of glucose. The result of all the process in cellular respiration is given by the equation:
C6H12O6 (aq) + 6 O2 (g) --> 6 CO2 (g) + 6 H2O (l) with an energy output of 2880 kJ per mole of glucose
The energy produced in cellular respiration is carried within the cell for other metabolic processes that need energy by ATP.