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Question #45184
The Question
The Genetic Engineering Appraisal Committee (GEAC) strictly evaluates the biosafety of introducing GM crops like Bt cotton, which expresses the cryIAc and cryIIAb genes. A major ecological concern is the potential for horizontal gene transfer to wild, weedy relatives. If such an introgression occurs, which of the following statements correctly describes the most probable ecological consequence?
Options
- A.
The weedy relative will acquire resistance to coleopteran pests, increasing its evolutionary fitness and disrupting the standing crop of the native ecosystem.
- B.
The weedy relative gains a significant fitness benefit by resisting lepidopteran herbivores, allowing it to outcompete native flora and alter the ecosystem's competitive dynamics.
- C.
The transgenic escapee will suffer reduced reproductive fitness because the alkaline pH required to activate the protoxin is absent in plant tissues.
- D.
The horizontal transfer will induce RNA interference (RNAi) in the weed, providing cross-resistance against nematode parasites like Meloidogyne incognita.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Cry1Ac|Evolutionary Ecology of Parasitism|Co-extinction Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that Bt crops are 'insect resistant' without distinguishing the specific insect orders targeted by specific cry genes (Lepidoptera vs Coleoptera).
Furthermore, this question requires synthesizing molecular genetics (cry gene specificity) with ecological concepts (evolutionary fitness and competitive exclusion) to understand the real-world risks of transgenic escape that justify GEAC oversight.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology and Its Applications - Class 12 |
| Concept | Cry Gene Specificity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |