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Question #46426
The Question
The Miller-Urey experiment demonstrated the abiotic synthesis of organic compounds under simulated primitive Earth conditions. Based on the thermodynamic constraints of chemical evolution and the Oparin-Haldane hypothesis, which of the following statements is INCORRECT?
Options
- A.
The experimental spark-discharge apparatus utilized a highly reducing gas mixture of CH4, H2, NH3, and water vapour at 800°C.
- B.
The eventual evolution of oxygenic photoautotrophs halted further chemical evolution by shifting the atmosphere from a reducing to an oxidizing state.
- C.
The rapid proliferation of early anaerobic chemoautotrophs (like methanogens) that consumed atmospheric H2 would have prolonged the abiotic synthesis of amino acids by stabilizing the reducing environment.
- D.
The absence of free oxygen (O2) in the primitive atmosphere was a critical prerequisite, as its presence would have rapidly oxidized the newly formed organic monomers.
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
CH4_H2|Methanobacterium|Early_Earth
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The 'Negative Feedback of Early Metabolism'.
Students often memorize that the early Earth was reducing and anaerobic, but fail to synthesize that early chemoautotrophs consuming H2 would actively destroy the very reducing conditions that allowed their abiotic precursors to form.
This tests the ability to link metabolic pathways with atmospheric shifts.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Miller-Urey Conditions |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |