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Question #46705
The Question
A researcher experimentally introduces a strong buffer into the stomach of a frog (Rana tigrina) immediately after it ingests an insect, rapidly shifting the gastric pH from 1.8 to 7.5. Which of the following will be the primary biochemical and physiological consequence of this sudden pH shift?
Options
- A.
The primary structure of pepsin is destroyed, preventing autocatalytic cleavage and causing free amino acid accumulation in the cardiac stomach.
- B.
Disruption of hydrogen and ionic bonds alters the active site geometry of gastric proteases, halting protein hydrolysis and causing macro-protein accumulation at the pyloric end.
- C.
Enterokinase is inhibited by the alkaline pH, preventing the conversion of pepsinogen to active pepsin and mimicking metabolic feedback failure.
- D.
The sudden alkalinity induces the optimal pH for salivary amylase, shifting the primary site of carbohydrate digestion to the stomach.
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
Frog Digestive Enzyme Specificity|Protein Denaturation Specificity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: This question tests the intersection of Biomolecules (protein denaturation) and Animal Physiology (digestion).
The primary misconception targeted is the level of protein structure affected by pH changes; students often forget that denaturation destroys secondary and tertiary structures (H-bonds/ionic bonds) but leaves the primary structure (peptide bonds) intact.
Additionally, it uses location and functional traps by misattributing enterokinase to the stomach and falsely introducing salivary amylase, which frogs do not possess.
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 |