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Question #45295
The Question
A researcher treats a dividing meristematic plant cell with colchicine to induce polyploidy. At the molecular level, this chemical prevents the progression of the cell cycle beyond metaphase. Which of the following is the primary molecular reason for this arrest?
Options
- A.
The Anaphase Promoting Complex (APC) remains inactive due to the lack of spindle tension at the kinetochores.
- B.
Colchicine binds to actin microfilaments, preventing the formation of the phragmoplast during cytokinesis.
- C.
The cell cycle arrests at the G2/M checkpoint because tubulin dimers cannot be synthesized.
- D.
Separase enzyme is prematurely activated, causing sister chromatids to separate without moving to opposite poles.
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
APC|Tubulin|Spindle_Fiber|Cell_Cycle
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'Colchicine causes metaphase arrest and polyploidy' but fail to connect it to the molecular checkpoint (APC inactivation).
The trap lies in confusing the structural target (tubulin vs. actin) and the sequence of enzyme activation (APC must activate before separase can cleave centromeres).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell Cycle and Cell Division - Class 11 |
| Concept | Anaphase Promotion Complex (APC) |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |