How does a glow worm glow?

[Santosh Kumar]

Can anyone give me a positive reply for my stupid quesition... Awaiting for UR response.. Mail me if U can to santoo_143 at rediff

[Anil]

Glow worms and fireflies exhibit a phenomenon called bioluminescence. These worms have a chemical, luciferin, stored under a transparent cuticle (a sort of exoskeleton), with an area of very dense tissue underneath which probably acts as a reflector. The light production is because of an oxidation reaction where the luciferin reacts with oxygen in the presence of the enzyme luciferase. This produces oxyluciferin and energy- which is emitted in the form of light. Later the oxyluciferin is transformed back into luciferin so that the process can be repeated. Since there is hardly any energy generated as heat (when compared to a candle or electric bulb) this is probably one of the most efficient means of generating light. The brightest fireflies produced light equivalent to only about 1/40th of a candle, but the light is emitted at a wavelength at which the human eye is very sensitive, so they may give off enough light to read a book. I don\'t know how true it is but I read somewhere that the bright fireflies found in China and Japan have been known to be used by poor students to read their books by!