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Question #46877
The Question
A researcher administers a broad-spectrum antibiotic to a population of Periplaneta americana, effectively eradicating their gut microbiome. Subsequently, the cockroaches exhibit a severe metabolic decline despite being fed a diet rich in plant matter. Which of the following best explains this physiological crisis and the anatomical structure whose functional efficiency is indirectly compromised?
Options
- A.
The antibiotic directly inhibits the secretion of digestive enzymes from the crop, preventing the initial biochemical breakdown of food.
- B.
The depletion of symbiotic bacteria prevents cellulose digestion, rendering the digestive juices of the hepatic caeca insufficient for complex carbohydrate assimilation.
- C.
The absence of gut flora drastically increases the Biochemical Oxygen Demand (BOD) within the haemolymph, leading to tracheal system failure.
- D.
The antibiotic degrades the thick cuticular lining of the foregut, causing the proventriculus to fail in mechanically grinding the plant matter.
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
Hepatic_Caeca|Cellulase_Activity|Symbiotic_Microflora
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating the anatomical function of the hepatic caeca (NCERT) with the physiological necessity of symbiotic bacteria for cellulose digestion.
The trap lies in Option C, which uses 'BOD' as a distractor to test if students can distinguish between an ecological concept (water pollution) and a physiological metabolic crisis, and Option D, which tests the exact nature of the proventriculus (mechanical, not bacterial).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Structural Organisation in Animals - Class 11 |
| Concept | Cockroach Alimentary Canal |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |