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Question #46395
The Question
A terrestrial ecosystem experiences a severe, prolonged drop in soil pH, which drastically inhibits the chemoautotrophic bacteria Nitrosomonas and Nitrobacter. Despite the resulting alterations in the nitrogen cycle, the ecosystem's terrestrial fauna maintain their standard modes of excretion. Which of the following statements regarding the nitrogen dynamics and excretory adaptations in this scenario is INCORRECT?
Options
- A.
The inhibition of Nitrosomonas prevents the oxidation of ammonia to nitrite, disrupting the primary pathway of nitrate formation for plant absorption.
- B.
The acidic soil conditions decrease the rate of decomposition, causing a bottleneck in the release of ammonia from dead biomass during ammonification.
- C.
To compensate for reduced environmental nitrogen turnover, terrestrial amphibians will adaptively revert to ammonotelism to bypass the ATP-intensive Ornithine cycle.
- D.
Mammals maintain ureotelism because the conversion of ammonia to urea, while metabolically expensive, is an obligatory adaptation to prevent lethal dehydration.
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
Ammonia|Urea|Decomposition Rate Modifiers|Ecosystem
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The evolutionary trade-off between metabolic energy expenditure and water conservation.
Students often correctly recall that ammonia excretion requires no ATP (unlike urea synthesis) and might assume organisms can switch back to save energy during environmental stress.
The misconception is failing to recognize that ammonotelism is strictly limited by water availability; in terrestrial habitats, the prevention of dehydration is an absolute physiological constraint that always overrides the ATP costs of the Ornithine cycle.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Excretory Products and Their Elimination - Class 11 |
| Concept | Nitrogenous Waste Classification |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |