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Question #46779
The Question
During an in vitro experiment, the local pH of the fluid surrounding a living animal cell is drastically altered to match the exact isoelectric point (pI) of its integral membrane ATPase pumps. Which of the following best describes the subsequent molecular and cellular events?
Options
- A.
The amino acid residues of the pump form zwitterions with maximum solubility, increasing the membrane's permeability to both and ions.
- B.
The integral proteins lose their amphipathic stabilization due to a net-zero charge, leading to protein precipitation, pump failure, and eventual osmotic lysis.
- C.
The pump undergoes a conformational lock, continuously extruding without hydrolyzing ATP, leading to severe cellular dehydration.
- D.
The disruption of hydrophobic interactions causes the integral proteins to become peripheral, converting active transport into facilitated diffusion.
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
Amino Acid Zwitterion Equilibrium | Plasma Membrane Fluidity | Active vs Passive Gradient Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Connecting the concept of the 'Zwitterionic state' from Biomolecules to 'Protein Denaturation/Solubility' and applying it to 'Membrane Transport'.
Students often mistakenly believe that a net-neutral zwitterion is the most stable and functional state, failing to realize that physiological proteins operate at a pH distinct from their pI to maintain solubility and prevent precipitation.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biomolecules - Class 11 |
| Concept | Amino Acid Zwitterion Equilibrium |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |