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Question #46966
The Question
A hypothetical mutation in a freshwater Euglenoid replaces its characteristic protein-rich outer layer with a rigid, silica-embedded cell wall analogous to that of diatoms. Which of the following would be the most direct physiological and ecological consequence of this structural alteration?
Options
- A.
The organism would exhibit enhanced metaboly due to the indestructible nature of the silica deposition, increasing its predatory efficiency.
- B.
The organism would lose its mixotrophic capability and become an obligate photoautotroph, as the rigid boundary prevents membrane invagination for phagotrophy.
- C.
The organism would become an obligate heterotroph, as the silica wall would completely block the penetration of photosynthetically active radiation (PAR).
- D.
The organism would maintain its mixotrophic niche but rely exclusively on osmotrophy in the dark, as the silica frustule facilitates the active transport of whole prey.
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
Dinoflagellate Bioluminescence and Toxins|Co-extinction Logic|Biotic Interactions
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that Euglenoids are 'mixotrophic' and possess a 'pellicle' as isolated facts.
This question forces the synthesis of these concepts by highlighting that the biomechanical flexibility of the proteinaceous pellicle is an absolute prerequisite for their heterotrophic (predatory) behavior.
A common misconception is failing to realize that rigid cell walls generally preclude endocytosis/phagocytosis across all taxa.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biological Classification - Class 11 |
| Concept | Dinoflagellate Bioluminescence and Toxins |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |