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Question #46896
The Question
During an in vitro recombinant DNA procedure, the restriction endonuclease EcoRI is used to cleave a purified plasmid in a cell-free buffer at 37°C. The reaction successfully hydrolyzes phosphodiester bonds at specific 5'-GAATTC-3' palindromic sites. Based on the defining criteria of life and the nature of this process, which of the following statements is strictly correct?
Options
- A.
The system represents a living organism because the highly specific, enzyme-mediated hydrolysis of phosphodiester bonds is an exclusive, defining property of life.
- B.
The process is a living reaction but the system is not a living thing, as it demonstrates biological catalysis but lacks cellular organization and homeostatic regulation.
- C.
The system is neither a living thing nor a living reaction, because restriction endonucleases in a cell-free medium follow purely thermodynamic chemical kinetics without metabolic integration.
- D.
The process is considered a self-sustaining metabolic pathway in vitro, as the enzyme continuously turns over the DNA substrate without requiring cellular machinery.
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
Defining Properties Criteria|Restriction Enzyme Cleavage Physics|Selectable Marker vs Cloning Site
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The distinction between a 'living reaction' (chemical catalysis by biological molecules) and a 'living thing' (requiring cellular organization and homeostasis).
Students often fall into the trap of either equating biological enzyme activity directly with life (Option A/D) or completely stripping it of its biological classification because it is in a test tube (Option C).
The question tests the exact NCERT nuance that isolated in vitro biochemical reactions are 'surely living reactions' but not 'living things.'
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | The Living World - Class 11 |
| Concept | Metabolism vs. In-vitro Reactions |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |