Carbon dioxide (CO2) is a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air (about 0.03 percent) and is absorbed by plants in photosynthesis.
A set of metabolic reactions taking place in cells to convert biochemical energy from nutrients into adenosine triphosphate (ATP), releasing waste products including CO2.
Stomata: Tiny openings or pores in plant leaves where carbon dioxide can enter for photosynthesis.