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Question #46216
The Question
In a coastal mangrove ecosystem, a sudden and prolonged rise in water level completely submerges the pneumatophores of Rhizophora. Which of the following sequences best describes the primary physiological cascade leading to immediate root tissue damage in this highly saline environment?
Options
- A.
Hypoxia → Shift to anaerobic respiration → ATP deficit → Failure of active Na+ exclusion → Ion toxicity
- B.
Waterlogging → Increased passive Na+ efflux → Loss of osmotic gradient → Exosmosis → Root plasmolysis
- C.
Hypoxia → Accumulation of toxic H2S from rhizosphere → Inhibition of lenticel opening → Cessation of gaseous exchange
- D.
High salinity → Inhibition of root pressure → Stomatal closure → Decreased photosynthetic rate → Starvation
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
Pneumatophores|Methanogens_Metabolism|Active_vs_Passive_Gradient
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often view morphological adaptations (pneumatophores) and physiological adaptations (halophytic osmoregulation) as isolated concepts.
The trap lies in failing to connect the morphological structure's metabolic purpose (ATP generation via aerobic respiration) to its critical role in surviving a secondary environmental stress (active ion exclusion in high salinity).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Root Modifications |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |