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Question #46431
The Question
In the context of the 'RNA World' hypothesis, early self-replicating ribozymes functioned without the buffering advantage of a degenerate genetic code. Which of the following best describes the primary evolutionary constraint imposed by this lack of degeneracy during early chemical evolution?
Options
- A.
Every point mutation would directly alter the functional structure of the ribozyme, leading to a high risk of mutational meltdown and restricting sequence complexity.
- B.
The absence of wobble base pairing would inherently increase the fidelity of RNA replication, preventing the generation of new variations.
- C.
Early RNA molecules would be unable to form phosphodiester bonds, halting the abiotic polymerization of nucleotides.
- D.
The ribozymes would immediately undergo reverse transcription to form double-stranded DNA to achieve structural stability.
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
RNA_World|Ribozymes|Degenerate_Codons
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between the chemical instability of RNA (due to the 2'-OH group) and the genetic instability of early replicators (due to the lack of a degenerate code).
Students often fail to realize that degeneracy is an evolutionary buffer against high mutation rates, a critical concept linking 'Molecular Basis of Inheritance' with 'Evolution'.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Chemical Evolution Sequence |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |