The light producing substance in glowworm fire fly is:

Correct option is B

In glowworms and fireflies (family: Lampyridae), bioluminescence is produced by a chemical reaction involving the light-producing molecule luciferin. This reaction occurs in specialized light-emitting organs, usually located in the abdomen, and is used for communication, especially mating signals.
�� Mechanism of Light Production in Fireflies:
· The primary light-producing substance is Luciferin.
· The enzyme that catalyzes the reaction is Luciferase.
· The reaction requires:
· Luciferin (substrate)
· Luciferase (enzyme)
· Oxygen
· ATP (energy molecule)
· The chemical reaction produces:
· Oxyluciferin
· Carbon dioxide
· Light (cold light) – nearly 90–98% efficient (very little heat produced)
Luciferin + O₂ + ATP → Oxyluciferin + CO₂ + Light
Explanation for Each Option
(a) Luciferase ❌
· This is the enzyme that catalyzes the reaction but does not produce light on its own.
· Without luciferin, no light is generated.
(b) Luciferin ✅
· Correct answer.
· It is the light-producing substrate that reacts in the presence of oxygen and luciferase to emit light.
(c) Lucithrin ❌
· Not a real biochemical compound related to bioluminescence.
· Distractor option.