Q60. Which one of the options given correctly matches the alkaloids in Group I with their source plants in Group II?
| Group I | Group II |
|---|---|
| P. Cocaine Q. Caffeine R. Morphine S. Atropine | 1. COCA 2. Nightshade 3. COCA 4. Poppy |
CSIR NET Life Sciences: Matching Alkaloids with Plants in Group I and II
The correct option is (A) P-3, Q-1, R-4, S-2, as it accurately pairs the Group I alkaloids (P: Cocaine, Q: Caffeine, R: Morphine, S: Atropine) with their corresponding plants in Group II (1: Coca, 2: Nightshade, 3: COCA, 4: Poppy).
Question Breakdown
Group I lists four alkaloids from plants: Cocaine (P), Caffeine (Q), Morphine (R), and Atropine (S). Group II provides plant sources: 1. Coca, 2. Nightshade, 3. COCA, 4. Poppy. Note that options 1 (Coca) and 3 (COCA) both refer to the coca plant (Erythroxylum coca), the primary source of cocaine.
Option Analysis
Option (A) P-3, Q-1, R-4, S-2: Correct. Cocaine from COCA (3), Caffeine from Coca (1, as it contains trace purine alkaloids alongside primary tropane alkaloids), Morphine from Poppy (4, Papaver somniferum), Atropine from Nightshade (2, Solanaceae family like Atropa belladonna).
Option (B) P-1, Q-3, R-4, S-2: Incorrect. Switches P and Q; while coca contains both cocaine (primary) and caffeine (trace), the standard primary match prioritizes cocaine for coca, not caffeine.
Option (C) Q-1, R-3, S-4: Incomplete (only three pairs) and wrong. Caffeine not primarily from coca; morphine not from COCA; atropine not from poppy.
Option (D) P-4, Q-2, R-1, S-3: Incorrect. Cocaine absent in poppy; caffeine absent in nightshade; morphine absent in coca.
Alkaloid-Plant Matches
| Alkaloid (Group I) | Primary Plant/Source (Group II) | Scientific Details |
|---|---|---|
| P: Cocaine | 3: COCA / 1: Coca | Erythroxylum coca leaves contain 0.5-1% cocaine. |
| Q: Caffeine | 1: Coca (trace) / Coffee/Tea primarily | Coca has minor caffeine; major sources are Coffea and Camellia sinensis. |
| R: Morphine | 4: Poppy | Papaver somniferum opium latex yields 8-19% morphine. |
| S: Atropine | 2: Nightshade | Solanaceae plants like Atropa belladonna and Datura stramonium. |
Cocaine, caffeine, morphine, and atropine represent key plant-derived alkaloids tested in CSIR NET Life Sciences exams under plant biochemistry and secondary metabolites. Matching alkaloids with plants like coca, nightshade, and poppy requires precise knowledge of biosynthetic sources, crucial for questions on pharmacognosy and natural products.
Alkaloid Sources in Plants
These alkaloids serve as plant defenses: tropane types (cocaine, atropine) deter herbivores, purine types (caffeine) inhibit competitors, and isoquinoline types (morphine) protect seeds.
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Cocaine: Exclusive to Erythroxylum coca (coca shrub); leaves yield tropane alkaloid via methylecgonone reductase enzyme.
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Caffeine: Primarily Coffea (coffee), Camellia sinensis (tea); trace in coca as purine alkaloid.
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Morphine: Papaver somniferum (opium poppy); 8-19% in latex.
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Atropine: Nightshade family (Solanaceae: Atropa belladonna, Datura stramonium); tropane alkaloid in roots/leaves.
CSIR NET Exam Strategy
Focus on primary associations: coca-cocaine, poppy-morphine, nightshade-atropine. Trace overlaps (e.g., caffeine in coca) test deeper recall but yield to dominant matches in MCQs. Practice with diagrams of alkaloid pathways for retention.
Biotechnological Relevance
Genetic engineering targets these pathways for pharmaceuticals; e.g., morphine biosynthesis in yeast via poppy genes. Understanding matching alkaloids with plants aids bioremediation and drug discovery questions.