When an enzyme called luciferase is present, oxygen reacts chemically with calcium, adenosine triphosphate (ATP), a chemical called luciferin, and other substances inside the firefly's light organ to produce light.
When an enzyme called luciferase is present, oxygen reacts chemically with calcium, adenosine triphosphate (ATP), a chemical called luciferin, and other substances inside the firefly's light organ to produce light.