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Question #46695
The Question
In Periplaneta americana, the compound eyes consist of approximately 2000 ommatidia, providing mosaic vision characterized by high sensitivity and low resolution. If an experimental neurotoxin that enhances inhibitory GABAergic modulation is applied to the optic ganglion, significantly increasing synaptic delay, what will be the most direct consequence on the insect's visual perception of a fast-moving object?
Options
- A.
Spatial resolution will increase because the prolonged synaptic delay allows for better integration of light stimuli.
- B.
Temporal resolution will decrease, lowering the flicker-fusion frequency and causing the object to be perceived as a continuous blur.
- C.
The ommatidia will physically shift their pigment sheaths to switch from apposition to superposition image formation.
- D.
Overall visual sensitivity will be lost because the delayed impulses will fail to undergo spatial summation in the brain.
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
Ommatidia|Action Potential Threshold Logic|Synaptic Delay
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between spatial resolution (anatomical limit of ommatidia) and temporal resolution (neural processing speed).
Students often confuse the NCERT line 'more sensitivity but less resolution' (which refers to spatial resolution) with the insect's ability to process fast motion (temporal resolution).
The trap lies in assuming that altering neural speed changes the optical physics of the eye (Option A and C) or completely halts spatial summation (Option D).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Structural Organisation in Animals - Class 11 |
| Concept | Mosaic Vision Processing |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |