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Question #45895
The Question
During a biolistic transformation experiment, a localized mutation is induced in the non-coding strand of a eukaryotic structural gene. This mutation alters the specific DNA sequence that corresponds to the 5' boundary of an intron in the primary transcript. Which of the following is the most likely consequence of this mutation?
Options
- A.
The spliceosome will fail to recognize the boundary, leading to exon skipping or intron retention and a drastically altered polypeptide.
- B.
The mutation will not affect the final mRNA because the coding strand, not the non-coding strand, acts as the template for hnRNA synthesis.
- C.
RNA polymerase III will prematurely terminate transcription at the mutated site, preventing translation.
- D.
The addition of methyl guanosine triphosphate at the 5' end of the hnRNA will be completely inhibited.
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
Spliceosome Mechanics|Non-Coding Strand Utility|Biolistics/Gene Gun Physics
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the nomenclature of DNA strands (Coding vs.
Non-coding/Template) and the specific roles of RNA polymerases.
The trap in Option B exploits the counter-intuitive NCERT fact that the 'non-coding' strand is actually the template strand that is transcribed.
Furthermore, it tests the understanding that splicing is sequence-dependent, and altering splice sites leads to exon skipping/intron retention rather than transcriptional termination.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Molecular Basis of Inheritance - Class 12 |
| Concept | Spliceosome Mechanics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |