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Question #46293
The Question
During the active opening of stomata, H+-ATPase pumps in the guard cell plasma membrane create an electrochemical gradient. If a metabolic inhibitor specifically blocks these pumps, which of the following sequences of events will occur, and what neurophysiological state does this failure most closely resemble?
Options
- A.
Failure of membrane hyperpolarization -> Prevention of K+ influx -> Stomata remain closed; resembles the loss of resting membrane excitability due to Na+/K+ pump failure.
- B.
Continuous membrane depolarization -> Massive K+ efflux -> Stomata open widely; resembles the peak of an action potential in a neuron.
- C.
Accumulation of protons in the apoplast -> Osmotic entry of water -> Stomatal opening; resembles the influx of Ca2+ at the axon terminal.
- D.
Failure of membrane hyperpolarization -> Active pumping of K+ out of the cell -> Stomata remain closed; resembles the refractory period of a nerve fiber.
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
Stomatal Apparatus Anatomy|Neural Control and Coordination|H+-ATPase
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'K+ influx causes stomatal opening' without understanding the bioenergetics (the H+ pump creates the electrical gradient required for K+ entry).
The trap lies in confusing the active vs. passive nature of these ion fluxes (H+ is active, K+ is passive down the induced gradient).
Furthermore, mapping plant electrophysiology to animal neurophysiology tests deep conceptual synthesis, specifically the role of ATPases in maintaining excitable gradients.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Anatomy of Flowering Plants - Class 11 |
| Concept | Stomatal Apparatus Anatomy |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |