Bioluminescence is the name given to the production and propagation of light by converting chemical energy into light energy during chemical reactions, performed by some living organisms. The term bioluminescence is etymologically derived from the Greek words "bios" (life) and Latin "lumen" (light). This chemical reaction can also be carried out by symbiotic organisms that live on large organisms. The name given to the chemical compound underlying the reaction is Luciferin. Light is produced and emitted when Luciferin is oxidized by the Luciferase enzyme. This chemical reaction can occur inside or outside the cell. In bacteria, the genes that allow bioluminescence to occur are controlled by the Lux Operon.