What is the oxygen cycle?

The oxygen cycle is the process by which plants absorb carbon dioxide during the day through microscopic pores on their leaves called stomata. When sunlight reaches the leaves, it starts a process called photosynthesis that requires carbon dioxide and other reactants. The products of photosynthesis include oxygen, sugar, and other substances. This process releases carbon dioxide into the atmosphere, where it is absorbed by animals and then recycled back into the atmosphere by plants for photosynthesis.

The oxygen cycle is the biogeochemical cycle that describes the movement of oxygen within the Earth's atmosphere, biosphere, and lithosphere. It involves processes such as photosynthesis, respiration, and decomposition, which collectively regulate the concentration of oxygen in the atmosphere and contribute to the maintenance of life on Earth.