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Question #45910
The Question
Methanobacterium, an archaebacterium found in the rumen of cattle, thrives in strictly anaerobic conditions. If a researcher analyzes its ATP production mechanism, which of the following statements correctly describes its Electron Transport System (ETS)?
Options
- A.
It relies entirely on substrate-level phosphorylation since an ETS cannot operate without O2 as the terminal electron acceptor.
- B.
It establishes a chemiosmotic gradient across its plasma membrane by utilizing CO2 as the terminal electron acceptor instead of O2.
- C.
It utilizes standard mitochondrial complexes I to IV located on mesosomes, with H2 acting as the terminal electron acceptor.
- D.
It possesses a modified Complex IV (cytochrome c oxidase) that reduces CO2 to methane directly in the cytoplasm.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Methanogens|Complex_I|Electron_Acceptors
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The assumption that ETS and chemiosmosis strictly require Oxygen.
Common Misconception: Students often conflate anaerobic respiration with fermentation, assuming that without O2, an organism must rely entirely on substrate-level phosphorylation.
They fail to recognize that anaerobic respiration uses a modified ETS on the plasma membrane with alternative terminal electron acceptors like CO2.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Respiration in Plants - Class 11 |
| Concept | ETS Complex Specificity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |