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Question #45181
The Question
Transgenic plants resistant to Meloidogyne incognita are created using Agrobacterium vectors to express nematode-specific dsRNA. Upon the plant's death, its detritus releases persistent recombinant DNA into the soil. If this DNA undergoes horizontal gene transfer into local saprophytic bacteria and inadvertently triggers RNAi-mediated silencing of their endogenous genes coding for extracellular hydrolytic enzymes, which specific step of decomposition will be directly impaired, and what will be the ecological consequence?
Options
- A.
Fragmentation; resulting in the accumulation of raw detritus and delayed humification.
- B.
Catabolism; resulting in a decreased rate of mineralization and locking of nutrients in complex organic forms.
- C.
Leaching; causing water-soluble inorganic nutrients to precipitate in the lower soil horizon.
- D.
Humification; accelerating the immediate release of inorganic nutrients into the standing state.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
RNAi Vector Source|Optimal Foraging Theory|Secondary Productivity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing the specific biological agents and mechanisms of the 5 steps of decomposition.
Students often confuse the roles of detritivores (fragmentation) with saprophytes (catabolism).
The question also tests the application of Horizontal Gene Transfer (HGT) as an ecological risk of transgenic detritus, forcing students to link molecular silencing (RNAi) directly to ecosystem-level nutrient cycling (mineralization).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology and Its Applications - Class 12 |
| Concept | RNAi Vector Source |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |