UPSC Prelims 2023 Q16: Geography – Indian Physical Geography
- (a) Only one
- (b) Only two
- (c) Only three
- (d) All four
Answer: (d) All four
Explanation
Properties of Mushrooms
| Statement | Property | Verdict | Examples |
|---|---|---|---|
| 1 | Medicinal properties | TRUE | Reishi (*Ganoderma lucidum*) — immune modulation. Chaga — antioxidant. Lion's Mane — neurological benefits. Turkey Tail — cancer adjunct therapy. |
| 2 | Psycho-active properties | TRUE | Psilocybe (magic mushrooms) contain psilocybin — a psychedelic compound. Amanita muscaria contains muscimol. Used in research for depression treatment. |
| 3 | Insecticidal properties | TRUE | *Beauveria bassiana*, *Metarhizium* — entomopathogenic fungi that infect and kill insects. Used as bio-insecticides in agricultural pest control. |
| 4 | Bioluminescent properties | TRUE | ~100 species of bioluminescent fungi exist (e.g., *Panellus stipticus*, *Mycena chlorophos*). They emit green/yellow light via luciferin-luciferase type reactions. |
All four properties exist in various mushroom species.
Answer: (d) All four.
Why each option is right or wrong
- (a) Incorrect. 'Only one' — multiple distinct categories of mushroom properties are well-documented scientifically.
- (b) Incorrect. 'Only two' — insecticidal and bioluminescent properties of fungi are real and well-studied.
- (c) Incorrect. 'Only three' — bioluminescent fungi are a documented phenomenon with ~100 known species.
- (d) CORRECT. All four properties — medicinal, psycho-active, insecticidal, and bioluminescent — are exhibited by different mushroom species.
Key point
All four mushroom properties are real: Medicinal (Reishi), Psycho-active (Psilocybe/psilocybin), Insecticidal (Beauveria/Metarhizium as bio-pesticides), Bioluminescent (~100 glowing fungal species). None is fabricated.
Remember
Mushrooms exhibit all four properties: medicinal (Reishi), psycho-active (psilocybin in Psilocybe), insecticidal (entomopathogenic fungi), and bioluminescent (~100 glowing fungal species worldwide).
Common mistakes
- Doubting bioluminescence in fungi — about 100 fungal species are confirmed bioluminescent, emitting soft green/yellow light in forests.
- Not knowing insecticidal fungi — entomopathogenic fungi like Beauveria bassiana are commercially used as biological pesticides.
- Underestimating mushroom diversity — fungi have evolved extraordinarily diverse chemical and physical properties.
Exam tip
All four mushroom properties = TRUE. Mnemonic: MPIB — Medicinal, Psycho-active, Insecticidal, Bioluminescent. UPSC often tests 'all four' or 'none' when the answer is counterintuitively comprehensive — verify each category before eliminating.
Sources
- NCERT Class XI Biology — Biological Classification (Kingdom Fungi)
- Paul Stamets — Mycelium Running: How Mushrooms Can Help Save the World (Ten Speed Press, 2005)