Before You Begin
Question #47708
The Question
Restriction endonucleases like SphI and BbuI are isolated from phylogenetically distant bacterial genera but recognize the exact same palindromic sequence (5'-CGTACG-3') to cleave bacteriophage DNA. Despite this functional identity, their amino acid sequences and protein domains share no significant similarity. Which of the following statements is NOT correct regarding this biological phenomenon?
Options
- A.
These enzymes represent analogous structures at the molecular level, resulting from convergent evolution.
- B.
The shared recognition sequence indicates that both bacterial strains faced similar selective pressures from specific viral genomes.
- C.
Their identical cleavage specificity proves they are homologous proteins derived from a common ancestral restriction-modification gene.
- D.
The nomenclature of these enzymes reflects their distinct taxonomic origins rather than a shared evolutionary lineage.
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
Transcriptional Unit Boundaries|Restriction Enzyme Cleavage Physics|Non-Coding Strand Utility
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse functional identity (recognizing the same palindromic sequence) with evolutionary homology.
The trap assumes that because two enzymes do the exact same highly specific job, they must share a common ancestral gene, ignoring the NCERT principle that different structures performing the same function define analogous organs and convergent evolution.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology : Principles and Processes - Class 12 |
| Concept | Restriction Enzyme Cleavage Physics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |