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Question #45149
The Question
Ecological management often employs biological control to avoid the broad-spectrum toxicity of chemical pesticides. However, the ecological consequences vary drastically depending on the strategy used. Which of the following statements regarding biological control and trophic dynamics is INCORRECT?
Options
- A.
Transgenic crops expressing the cryIAb gene preserve non-target biodiversity because the endotoxin's activation requires an alkaline pH and specific epithelial receptors unique to target pests like the corn borer.
- B.
Unlike chemical pesticides, the introduction of exotic species for biological control is inherently ecologically safe, as alien predators naturally restrict themselves to narrow ecological niches without disrupting native trophic cascades.
- C.
Unlike targeted transgenic bio-control, the introduction of alien species can trigger the 'Evil Quartet', leading to the decline of indigenous species due to the absence of natural predators in the new habitat.
- D.
While organic farming sustains native predator-prey oscillations to manage pests, the introduction of exotic species like the Nile perch into Lake Victoria demonstrates how alien invasions can cause the catastrophic extinction of unique indigenous assemblages.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Cry Gene|Bacillus thuringiensis|Alien Species Invasion
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often harbor the misconception that 'Biological Control' is universally synonymous with 'Ecological Safety'.
The trap exploits this by conflating the highly targeted, narrow-spectrum nature of Cry gene endotoxins with the unpredictable, broad-spectrum risks of introducing exotic species.
It tests the student's ability to synthesize Biotechnology (specificity of Bt toxins) with Biodiversity and Conservation (the 'Evil Quartet' and the dangers of Alien Species Invasions).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology and Its Applications - Class 12 |
| Concept | Transgenic Animal Purpose |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |