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Question #45923
The Question
When a mammalian skeletal muscle cell experiences severe hypoxia, it shifts from aerobic respiration to lactic acid fermentation. Which of the following metabolic consequences does NOT occur during this shift?
Options
- A.
Cessation of metabolic water formation at Complex IV due to the absence of the terminal electron acceptor.
- B.
Continuous regeneration of NAD+ within the mitochondrial matrix to sustain substrate-level phosphorylation in the TCA cycle.
- C.
Alteration of the mitochondrial inner membrane osmotic potential due to the collapse of the proton motive force.
- D.
Reoxidation of NADH + H+ in the cytoplasm catalyzed by the enzyme lactate dehydrogenase.
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
Metabolic_Water_Formation|Alcoholic_Beverage_Fermentation_Source|NADH_Recycling
Why This Question Is Tricky
Common Mistakes
Location Trap & Process Sequence: The conceptual pivot is understanding that while oxygen is not directly used in the TCA cycle, the cycle strictly requires NAD+ and FAD regenerated by the ETS.
Students often know fermentation regenerates NAD+, but fail to recognize this occurs exclusively in the cytoplasm, leaving the mitochondrial matrix depleted of NAD+ and halting the TCA cycle.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Respiration in Plants - Class 11 |
| Concept | Metabolic Water Formation |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |