What makes a firefly or lightning bug light up?

Answer 1

A firefly flashes when oxygen, breathed in through the abdominal tracheae, is allowed to combine with a substance called luciferin under the catalytic effect of the enzyme luciferase. This reaction produces a very efficient light, with almost no energy lost as heat. The timing of the firefly's flashes is controlled by the abundant nerves in the insect's light-making organ. The duration of the flashes depends on how long the luciferin takes to oxidize.
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Answer 2

It's a chemical reaction that is in an equilibrium (meaning it goes back and forth between one for and another), The reaction is heat dependent.
"Fireflies or lightning bugs make light within their bodies. This process is called bioluminescence and is shared by many other organisms, mostly sea-living or marine organisms. Fireflies light up to attract a mate. To do this, the fireflies contain specialized cells in their abdomen that make light.
The cells contain a chemical called luciferin and make an enzyme called luciferase. To make light, the luciferin combines with oxygen to form an inactive molecule called oxyluciferin. The luciferase speeds up the reaction, which occurs in two steps:

The luciferin combines with adenosine triphosphate (ATP), which is found in all cells, to form luciferyl adenylate and pyrophosphate (PPi) on the surface of the luciferase enzyme. The luciferyl adenylate remains bound to the enzyme:

luciferin + ATP -------------> luciferyl adenylate + PPi

The luciferyl adenylate combines with oxygen to form oxyluciferin and adenosine monophosphate (AMP). Light is given off and the oxyluciferin and AMP are released from the enzyme's surface:

luciferyl adenylate + O2 -------------> oxyluciferin +AMP + light

The wavelength of light given off is between 510 and 670 nanometers (pale yellow to reddish green color). The cells that make the light also have uric acid crystals in them that help to reflect the light away from the abdomen. Finally, the oxygen is supplied to the cells through a tube in the abdomen called the abdominal trachea. It is not known whether the on-off switching of the light is controlled by nerve cells or the oxygen supply.
The luciferin-luciferase chemical reaction has been used for years to measure the amount of ATP produced in cells and by various chemical reactions. Recently, the gene (section of DNA coding for the protein) for the luciferase enzyme has been isolated, placed in the genes of other organisms, and used to follow the synthesis and/or expression of other genes (i.e. used as a reporter gene)."

Answer 3

A chemical reaction takes place with the special "goop" in their, uh, backside. When the bug's natural electrical energy traveling down it's spine reaches the chemical goop, it lights up. Kind of like a fluorescent light.

Edit: Bugs don't have spines, I'm just hypothetically speaking

Answer 4

When i was 5 y.o my sister and i used to sit near a clump of bamboos after dinner at night and watch fireflies and i was thinking the same thing then, they are a mystery tome even now.

Answer 5

bioluminescene. its a pretty interesting process as described above.

added info: its almost the same with the principle of chemiluminescence which applies to highlighters and glow in the dark objects along with luminol (chemical they use for detecting blood in crime scenes). its quite fascinating if you ask me. :)

Answer 6

chemical energy to light energy. simple process