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Question #46975
The Question
Cyclosporin A, an immunosuppressive agent obtained from Trichoderma polysporum, inhibits calcium-dependent signaling pathways. While primarily known to suppress T-cell activation, this inhibition also severely impairs the amoeboid movement of macrophages. Which of the following best explains the cellular basis of this impaired locomotion?
Options
- A.
Inability to assemble tubulin dimers into microtubules, preventing the formation of an axoneme.
- B.
Failure of calcium-mediated actin cytoskeleton remodeling, trapping the cytoplasm in a stable gel state and preventing pseudopodia extension.
- C.
Disruption of dynein motor proteins, preventing the sliding of microfilaments required for protoplasmic streaming.
- D.
Inhibition of intermediate filament polymerization, causing the structural collapse of the cell membrane during diapedesis.
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
Cilia|Flagella|Tubulin_Polymerization
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students typically memorize Cyclosporin A strictly as a T-cell immunosuppressant (Microbes in Human Welfare) and amoeboid movement as a microfilament-driven process (Locomotion and Movement).
The pivot requires synthesizing these concepts by recognizing that calcium-dependent signaling bridges immune cell activation and the actin-driven sol-gel transformation.
A common misconception is confusing the specific cytoskeletal elements (Actin vs.
Tubulin) responsible for different types of cellular locomotion.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biological Classification - Class 11 |
| Concept | Protozoan Locomotory Organs |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |