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Q107 (CDS-II/2011) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Applied everyday chemistry Answer Verified

Fire fly gives us cold light by virtue of the phenomen of ’

Result
Your answer:  ·  Correct: C
Explanation

Fireflies produce light through a biological chemical reaction known as bioluminescence [c1][t1]. Bioluminescence is a specific form of chemiluminescence, which is defined as the emission of light resulting from a chemical reaction rather than heat or energy absorption [t2][t3]. In fireflies, this process involves the oxidation of a substrate called luciferin, catalyzed by the enzyme luciferase [t1][t5]. This reaction is highly efficient, converting nearly all energy into light with minimal heat production, earning it the name 'cold light' [t2][t3]. Unlike fluorescence or phosphorescence, which require the absorption and re-emission of external electromagnetic radiation, chemiluminescence generates light internally through chemical energy [t1][t3][t4]. Effervescence, conversely, refers to the escape of gas from an aqueous solution and is unrelated to light emission.

Sources

  1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 5: Changes Around Us: Physical and Chemical > FASCINATING FACTS > p. 63
  2. [2] https://pmc.ncbi.nlm.nih.gov/articles/PMC10861286/
  3. [3] https://education.nationalgeographic.org/resource/bioluminescence/
  4. [4] https://www.britannica.com/science/How-Do-Fireflies-Light-Up
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