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Question #46709
The Question
In a hypothetical experiment, the gene encoding pepsinogen in a frog is placed under a regulatory system identical to the bacterial lac operon. A mutation occurs in this system that is strictly analogous to the operator-constitutive () mutation. Assuming the cellular translation and secretion pathways remain intact, which of the following statements accurately predicts the physiological outcome in the frog's gastric mucosa?
Options
- A.
The chief cells will undergo immediate intracellular lysis because the continuously synthesized pepsin will digest the internal structural proteins.
- B.
Pepsinogen will be continuously secreted into the gastric lumen, but it will not cause autodigestion of the stomach lining unless activated by HCl secreted by oxyntic cells.
- C.
The mutation will cause the repressor protein to bind irreversibly to the operator, leading to a complete absence of pepsinogen and subsequent protein malnutrition.
- D.
The continuously secreted pepsinogen will undergo spontaneous autoactivation at a neutral pH, overwhelming the mucus neck cells and causing severe gastric ulcers.
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
Frog Digestive Enzyme Specificity|Lac Operon Inducibility
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: This question forces the integration of the Molecular Basis of Inheritance with Human/Animal Physiology.
Students often equate the 'overexpression of a protease gene' with 'immediate cellular destruction'.
The trap relies on forgetting the physiological safety mechanism taught in NCERT: gastric proteases are synthesized as inactive zymogens specifically to prevent autodigestion, and their activation is spatially and chemically regulated by HCl.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Structural Organisation in Animals - Class 11 |
| Concept | Frog Digestive Enzyme Specificity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |