In the process of photosynthesis, plants use carbon dioxide (CO2), water (H2O), and light energy to produce sugar (C6H12O6) and oxygen (O2). In the process of aerobic respiration, animals and plants release energy from sugar and oxygen and produce carbon dioxide and water. The chemical equations that describe these reactions look like this: 6CO2 + 6H2O + light C6H12O6 + 6O2 C6H12O6 + 6O2 6CO2 + 6H2O + energy

How do these equations explain why the total amount of O2 and CO2 remains the same?