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Question #45893
The Question
A targeted mutation in a human pancreatic -cell line completely inhibits the function of small nuclear ribonucleoproteins (snRNPs). Which of the following represents the most accurate consequence of this defect on insulin production?
Options
- A.
The hnRNA of the insulin gene will retain introns, leading to the synthesis of a truncated polypeptide or degradation of the transcript.
- B.
The proinsulin polypeptide will fail to undergo cleavage of the C-peptide, resulting in the accumulation of non-functional insulin.
- C.
RNA polymerase II will prematurely terminate transcription, failing to synthesize the complete primary transcript.
- D.
The transcript will lack a 3' poly-A tail, preventing its exit from the nucleus to the cytoplasm.
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
Spliceosome Mechanics|Insulin Chain Maturation|Alpha-1 Antitrypsin
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The question tests the student's ability to distinguish between RNA splicing (removal of introns from hnRNA) and protein maturation (removal of the C-peptide from proinsulin).
A common misconception is conflating the 'processing' of hnRNA to mRNA with the 'processing' of proinsulin to mature insulin, as both involve the excision of an intermediate segment.
The trap (Option B) exploits this functional overlap in terminology.
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 |