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Question #45111
The Question
A wild plant population is in Hardy-Weinberg equilibrium. A few transgenic individuals, developed via disarmed Agrobacterium tumefaciens Ti-plasmid vectors, are introduced into this habitat. They carry a novel dominant allele (R) conferring absolute resistance to a newly emerged, lethal fungal pathogen. Which of the following statements is INCORRECT regarding the evolutionary trajectory of this population?
Options
- A.
The T-DNA insertion mimics a sudden mutation and acts as gene flow, immediately violating the HWE assumptions.
- B.
The lethal fungal pathogen exerts strong directional selection, causing a rapid increase in the frequency of the R allele.
- C.
Because the R allele is dominant and confers absolute survival, the wild-type recessive allele (r) will be completely eliminated from the gene pool in a single generation.
- D.
The Agrobacterium-mediated gene transfer effectively bypasses natural Mendelian assortment to introduce the novel allele into the gene pool.
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
Agrobacterium_Tumefaciens|Selection_Pressure|Genetic_Drift|Allele_Frequency
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the 'elimination of a phenotype' with the 'elimination of an allele'.
A common misconception is that absolute selection against a recessive trait instantly purges the allele from the gene pool, forgetting that heterozygotes act as a reservoir for recessive alleles.
This question forces the synthesis of Agrobacterium-mediated transformation as an evolutionary driver (mutation/gene flow) that disrupts HWE.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology : Principles and Processes - Class 12 |
| Concept | Agrobacterium Tumefaciens Mechanism |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |