Cellular respiration.

The most basic difference, and indeed, the defining difference, between aerobic and anaerobic processes is simply the use of oxygen. Depending on the process, the end result may be very similar, or entirely different, but aerobic processes mean that it uses the oxygen, while anaerobic means it doesn't.

The pig iron is converted into steel through a process called the basic oxygen steel making.

The basic process of photosynthesis is the sun is absorbed by the plants chloroplasts and is combined with carbon dioxide and water. The plant is then able to create a chemical reaction with the water, carbon dioxide and sunlight and creates oxygen and glucose. The significance of photosynthesis is to make oxygen for other organisms to live and for plants to be able to make their own energy.

oxygen