Final answer:
Photosynthesis is the process that consumes oxygen and produces oxygen. It is vital for sustaining life on Earth.
Step-by-step explanation:
Photosynthesis is the process that consumes oxygen. Plants use the oxygen from the air in respiration and also release carbon dioxide, but during the process of photosynthesis, they consume carbon dioxide and produce oxygen.
This is a vital process for sustaining life on Earth as it provides the oxygen we need. An example of the reaction involved in photosynthesis is:
6CO2 + 6H2O + light energy → C6H12O6 + 6O2