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Question #46119
The Question
In a developmental biology experiment on Periplaneta americana, a mutation is induced causing the Hox genes responsible for abdominal segment identity to be ectopically expressed in the thoracic segments. Based on the structural organization of the cockroach, which of the following physiological anomalies is the most direct consequence of this homeotic transformation?
Options
- A.
Inability to mechanically grind food particles due to the failure of the proventriculus to develop six highly chitinous plates.
- B.
Accumulation of uric acid in the haemolymph due to the absence of Malpighian tubules at the foregut-midgut junction.
- C.
Failure of chemical digestion due to the inability of the mesenteron to secrete a thick cuticular lining.
- D.
Impaired water reabsorption due to the transformation of the hindgut into a non-cuticular, absorptive structure.
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
Cockroach_Alimentary_Canal|Segmentation|Hox_Genes
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating developmental biology (homeotic mutations) with NCERT structural anatomy of the cockroach.
The question tests the student's ability to map the proventriculus to its anterior/thoracic origin and its mechanical function (chitinous teeth).
It also utilizes a high-frequency NEET 'Location Trap' in Option B by misplacing the Malpighian tubules, forcing students to recall exact anatomical junctions.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Segmentation vs. Metamerism |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |