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Question #46085
The Question
In an ex-situ conservation facility, a batch of threatened plant germplasm stored in liquid nitrogen (-196°C) experiences a sudden, prolonged breach in thermal insulation, returning the samples to ambient temperature. Which of the following physiological events primarily drives the rapid loss of viability and subsequent degradation of the germplasm in this scenario?
Options
- A.
Mechanical rupture of the plasma membrane due to the formation of intracellular ice crystals during the temperature rise.
- B.
Reactivation of endogenous hydrolytic enzymes and microbial proliferation facilitated by increased liquid water availability.
- C.
Irreversible denaturation of cellular enzymes caused by the rapid transition from cryogenic to ambient temperatures.
- D.
Depletion of intracellular ATP reserves due to the sudden hyperactivation of membrane-bound ion pumps.
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
Sacred Groves as Refugia|Ecological Succession Climax|Diversity-Stability Relationship
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that cryopreservation preserves cells at -196°C but fail to understand the underlying mechanism (arresting metabolism by removing liquid water).
The common misconception is confusing the mechanical damage of improper freezing (ice crystal formation) with the biological degradation of thawing (enzymatic/microbial decay due to restored water activity).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biodiversity and Conservation - Class 12 |
| Concept | Sacred Groves as Refugia |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |