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Question #46270
The Question
A mutant angiosperm undergoes normal double fertilization, but produces 'empty', non-viable seeds lacking essential storage proteins. Molecular analysis of the developing endosperm reveals a defect in the tRNA anticodon loop, completely abolishing the 'wobble' base-pairing mechanism. Which of the following best explains the direct cause of developmental arrest in these seeds?
Options
- A.
The loss of translational degeneracy prevents the recognition of synonymous codons, stalling the elongation of storage polypeptides.
- B.
The mutation induces a frameshift error during mRNA synthesis, leading to premature termination of storage protein transcripts.
- C.
Aminoacyl-tRNA synthetases lose their specificity, causing incorrect amino acids to be incorporated into the seed storage proteins.
- D.
The primary endosperm cell fails to absorb nutrients from the nucellus due to the disruption of maternal morphological signaling.
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
Seed Embryology|Genetic Code Degeneracy|Nucleic Acid Structural Stability
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'degeneracy' and the 'wobble hypothesis' as abstract molecular concepts without linking them to physiological consequences.
The trap tests the ability to distinguish between translational elongation defects (wobble/codon recognition) versus transcriptional errors (frameshifts) or tRNA charging defects (synthetase specificity) in the context of plant embryogeny.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Seed Embryology |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |