The breakdown reactions ... oxygen. If oxygen is available to the cell then the pyruvate molecules can be further broken down in stage two to release more energy and produce a greater quantity of ATP.

The end products of this chemical reaction ... oxygen around, in a process known as anaerobic respiration. This is much less efficient than the aerobic version, producing only two molecules of ATP ...

Fireflies produce a chemical reaction inside their bodies ... example of bioluminescence. When oxygen combines with calcium, adenosine triphosphate (ATP) and the chemical luciferin in the presence ...