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Question #45261
The Question
In a mammalian cell culture, a researcher experimentally accelerates the S-phase, causing DNA polymerase activity to significantly outpace the translation of basic amino acid-rich proteins. Which of the following is the most likely chromosomal consequence during the subsequent M-phase, and what is the precise mechanistic reason?
Options
- A.
Polyploidy, due to the failure of cytokinesis following improper chromatin condensation.
- B.
Aneuploidy, due to mechanical instability of the kinetochore leading to non-disjunction of sister chromatids.
- C.
Polyteny, due to repeated cycles of DNA replication without the formation of the 30 nm chromatin fiber.
- D.
Aneuploidy, due to the failure of the cell to replicate its entire genome before entering the G2 phase.
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
Histone Octamer Charge Interaction|Aneuploidy vs Polyploidy|Interphase Duration Paradox
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Linking molecular stoichiometry in S-phase to macroscopic chromosomal aberrations.
Students often fail to distinguish the exact mechanical causes of Aneuploidy (segregation failure due to spindle/condensation issues) versus Polyploidy (cytokinesis failure).
The trap relies on the student knowing that histones are synthesized in S-phase and deducing that a lack of histones disrupts condensation, which specifically triggers non-disjunction rather than whole-genome duplication.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell Cycle and Cell Division - Class 11 |
| Concept | Interphase Duration Paradox |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |