Before You Begin
Question #46411
The Question
Satellite DNA comprises highly repetitive sequences that form the bulk of constitutive heterochromatin in regions such as centromeres. If an epigenetic anomaly causes severe hyper-methylation of the centromeric satellite DNA in a dividing human somatic cell, which of the following is the most likely direct consequence?
Options
- A.
Activation of satellite DNA transcription, leading to the accumulation of non-coding RNA.
- B.
Disruption of kinetochore assembly, resulting in mitotic nondisjunction and aneuploidy.
- C.
Premature shortening of telomeres, triggering immediate cellular senescence.
- D.
Increased frequency of homologous recombination in the centromeric regions.
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
Satellite DNA|Heterochromatin|DNA Methyltransferase
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often restrict the role of DNA methylation strictly to 'gene silencing' (transcriptional regulation).
The misconception is failing to recognize that in non-coding structural regions like centromeric satellite DNA, epigenetic alterations disrupt physical chromosomal architecture (kinetochore assembly), leading to mechanical failures during cell division (nondisjunction) rather than just transcriptional changes.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Molecular Basis of Inheritance - Class 12 |
| Concept | Human Genome Repetitive DNA |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |