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Question #45968
The Question
In a plant tissue culture experiment, a callus is transferred to a nutrient medium containing a high Cytokinin to Auxin ratio to induce shoot organogenesis. Simultaneously, a highly specific chemical inhibitor that prevents the assembly of the phragmoplast is added to the medium. Which of the following best describes the most likely cellular consequence and its effect on morphogenesis?
Options
- A.
The cells undergo normal karyokinesis but fail to form a cell plate, resulting in a syncytium that prevents the spatial perception of morphogenic gradients, thereby halting shoot differentiation.
- B.
The cells arrest in the metaphase of mitosis due to the disruption of the mitotic spindle, preventing both karyokinesis and subsequent shoot differentiation.
- C.
Cytokinesis proceeds via cleavage furrow formation instead of a cell plate, allowing shoot organogenesis to occur but resulting in structurally compromised tissues.
- D.
The high Cytokinin-Auxin ratio overrides the structural inhibition, forcing the multinucleate cells to undergo rapid differentiation into multiple adventitious shoot buds.
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
Cytokinin|Auxin|Cell_Plate|Phragmoplast
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'High Cytokinin = Shoot differentiation' and 'Cytokinesis failure = Syncytium' as isolated NCERT facts.
The trap lies in failing to synthesize these concepts: realizing that hormonal morphogenic cues strictly require cellular compartmentalization (cell walls) to establish the spatial gradients necessary for tissue-specific gene expression.
Option D acts as a 'Common Half-Truth' distractor for students who over-prioritize the hormonal ratio over structural cellular prerequisites.
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 |