4 LIGHT MAKERS From fireworks to light sticks we love things that shine in the dark So does nature Did you know that hundreds of living organisms can glow These plants and animals turn the chemical energy stored in their tissues into light This is called bioluminescence pronounced bye-oh-loo-muh-nes uhns The light they create is a very efficient light or cold Comb jellies which are actually a type of plankton make bright pulses of light when they are disturbed
5 light This means that bioluminescent organisms produce mostly light and almost no heat A regular incandescent light bulb makes more heat than light Some organisms that glow use biofluorescence pronounced bye-oh-floo-res uhns These organisms absorb light from another source such as the Sun and then reemit that light as a different color Usually these creatures glow green or red Scien tists are studying ways to use fluorescence in science and medicine Whether they are bioluminescent or use biofluores cence organisms that glow in the dark are fascinating to see Organisms are living things made of one or more cells that are able to grow and reproduce VOCABULARY In normal light this deep-sea coral doesn’t look unusual But under a special light filter it fluoresces green
6 HOW DOES BIOLUMINESCENCE WORK Bioluminescent organisms make their own light through a chemical reaction in their bodies A chemical reaction is a process in which one or more sub stances are changed to one or more different substances The reactions that allow organisms to create light require the element oxygen and two special chemicals One is a substance called luciferin The other is an enzyme called luciferase Luciferin reacts with oxygen to create energy in Up close this is what the luciferase enzyme of a type of marine bacteria would look like
7 Fireflies can control how long and how often they flash their light Why is this important THINK ABOUT IT the form of light Luciferase triggers the reaction between the oxygen and luciferin Some organisms including fireflies also use energy from a substance called adenosine triphosphate or ATP to make light All living things including people get energy from the ATP in their cells Fireflies and many other organisms can regulate their chemistry This lets them control when they light up and how long their light lasts Each type of firefly has its own pattern of flashes Fireflies use the flashes to attract a mate