📘 Q.8 IAS Prelims 2025 — Science & Technology (Basic Science: Plant Morphology)
🧷 Authentic Classroom Explanation by IAS Monk
📌 The Question:
Consider the following pairs:
| Plant | Description |
|---|---|
| I. Cassava | Woody shrub |
| II. Ginger | Herb with pseudostem |
| III. Malabar spinach | Herbaceous climber |
| IV. Mint | Annual shrub |
| V. Papaya | Woody shrub |
How many of the above pairs are correctly matched?
(a) Only two
(b) Only three
(c) Only four
(d) All the five
✅ Answer:
(b) Only three
🧑🏫 Authentic Classroom Explanation:
🔹 Pair I: Cassava — Woody shrub ✔️
Cassava (Manihot esculenta) is a woody shrub belonging to the family Euphorbiaceae. It has a lignified stem and is cultivated mainly for its starchy tuberous roots (tapioca).
✅ Correctly matched
🔹 Pair II: Ginger — Herb with pseudostem ✔️
Ginger (Zingiber officinale) is a perennial herb. The apparent “stem” seen above ground is actually a pseudostem formed by tightly overlapping leaf bases.
✅ Correctly matched
🔹 Pair III: Malabar spinach — Herbaceous climber ✔️
Malabar spinach (Basella alba) is a soft-stemmed, herbaceous climber. It climbs using twining stems and is not woody in nature.
✅ Correctly matched
🔹 Pair IV: Mint — Annual shrub ❌
Mint (Mentha species) is not a shrub and not annual. It is a perennial herb that spreads through underground rhizomes and stolons.
❌ Incorrectly matched
🔹 Pair V: Papaya — Woody shrub ❌
Papaya (Carica papaya) looks tree-like but is botanically a large herb, not woody. Its stem is soft, hollow, and non-lignified.
❌ Incorrectly matched
📌 Thus, only Pairs I, II and III are correct → 3 pairs.
🔍 Curiosity Raiser:
Why does papaya look like a tree but behave like a herb? 🌱
👉 Because appearance doesn’t decide classification — internal tissue structure does. UPSC loves this trap.
🧠 Enrichment Notes (Prelims Edge):
- Woody vs Herbaceous depends on lignification, not size
- Pseudostem = leaf bases (banana, ginger)
- Many “tree-like” plants (papaya, banana) are giant herbs
- Mint’s aggressive spread is due to rhizomes, not seeds
📌 High-frequency UPSC zones: pseudostem, rhizome, woody vs herb
🪔 IAS Monk Whisper:
“In biology, form deceives — structure decides.”