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Question #46135
The Question
In an experimental setup, a marine biologist applies a localized neuro-inhibitor to the apical sensory organ (statocyst) of a living Pleurobrachia (Phylum Ctenophora). Which of the following best describes the immediate effect on the organism's locomotion?
Options
- A.
Complete cessation of ciliary movement, as the comb plates are entirely dependent on motor neurons for generating the power stroke.
- B.
Asynchronous beating of the eight ciliated comb rows, resulting in a loss of spatial orientation and directed movement.
- C.
Unaffected coordinated locomotion, because ciliary movement in ctenophores is strictly an autonomous, myogenic process.
- D.
Simultaneous reversal of the ciliary beat direction across all comb plates to initiate an escape response.
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
Ctenophora Locomotion|Neural Regulation Feedback|Feedback Mechanism Loops
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between the intrinsic ability of a cilium to beat and the systemic neural coordination required for directed locomotion.
The trap relies on the common misconception that ciliary movement in simple invertebrates (like Ctenophores) is entirely autonomous, similar to protozoans like Paramecium, ignoring the evolutionary emergence of the nerve net for sensory-motor integration.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Ctenophora Locomotion |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |