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Question #45112
The Question
Both Agrobacterium tumefaciens and Rhizobium species interact with the root cortical cells of dicotyledonous plants, establishing a metabolic sink. In a scenario where both microbes compete for the same wounded root niche, which of the following statements is INCORRECT regarding their infection mechanisms?
Options
- A.
Agrobacterium senses host-secreted phenolic compounds to activate its vir genes, while Rhizobium senses host-secreted flavonoids to synthesize Nod factors.
- B.
Both microbes induce the dedifferentiation and rapid division of inner cortical and pericycle cells to form their respective macroscopic root structures.
- C.
To establish their respective metabolic sinks, both microbes permanently integrate a specific segment of their plasmid DNA into the host plant's nuclear genome.
- D.
Rhizobium utilizes host-derived photosynthates to fuel the ATP-intensive nitrogenase enzyme, whereas Agrobacterium forces the host to synthesize opines for its exclusive nourishment.
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
Rhizobium|Agrobacterium|Niche_Overlap|Climax_Community
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate 'plasmid-mediated interactions' with 'genetic transformation'.
Because Rhizobium utilizes a Sym-plasmid (containing nod and nif genes) and Agrobacterium utilizes a Ti-plasmid, students falsely assume both integrate DNA into the host to cause cellular proliferation.
The trap tests the fundamental difference between genetic transformation (Agrobacterium's parasitism) and intracellular accommodation (Rhizobium's mutualism).
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 |