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Question #45967
The Question
A researcher genetically engineers a tomato callus to constitutively express antisense RNA against the enzyme polygalacturonase, utilizing the same molecular strategy seen in the 'Flavr Savr' variety. The callus is then transferred to a tissue culture medium containing a high Cytokinin to Auxin ratio. Which of the following best describes the most likely developmental outcome?
Options
- A.
Normal shoot emergence occurs because polygalacturonase is exclusively involved in fruit ripening and has no role in vegetative organogenesis.
- B.
Root initiation occurs instead of shoot initiation because the antisense RNA neutralizes the morphogenic effect of cytokinins.
- C.
Shoot differentiation is signaled, but physical shoot emergence from the callus is hindered due to the failure of middle lamella softening.
- D.
The callus undergoes rapid, undifferentiated proliferation because the RNA interference blocks the translation of both auxin and cytokinin receptors.
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
Auxin|Cytokinin|PG_Enzyme|Polygalacturonase
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often compartmentalize NCERT facts, associating high Cytokinin:Auxin strictly with successful shoot formation, and Flavr Savr/polygalacturonase strictly with delayed fruit ripening.
The trap lies in failing to synthesize these concepts: realizing that the physical emergence of organs in tissue culture requires the exact same cell wall loosening (pectin degradation in the middle lamella) that is targeted and suppressed in Flavr Savr tomatoes.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Growth and Development - Class 11 |
| Concept | Cytokinin-Auxin Ratio |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |