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Question #46724
The Question
Organisms must maintain physiological homeostasis despite environmental thermal stress. Which of the following statements is INCORRECT regarding the cellular and evolutionary adaptations to low temperatures?
Options
- A.
In poikilotherms, severe cold induces lipid crystallization in the plasma membrane, which directly inhibits the conformational changes of transmembrane carrier proteins like the Na+/K+ ATPase.
- B.
To prevent cold-induced metabolic arrest, cells undergo homeoviscous adaptation by increasing the proportion of unsaturated fatty acids in their membrane phospholipids.
- C.
The quasi-fluid nature of the lipid bilayer, which is compromised during thermal stress, is essential for functions like cell growth, secretion, and endocytosis.
- D.
According to Allen's Rule, endothermic mammals adapt to cold climates by evolving larger extremities to increase their surface area-to-volume ratio, thereby optimizing heat retention.
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
Phospholipid_Bilayer|Cholesterol_Buffer|Allen’s_Rule_Surface_Volume
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating micro-level membrane biophysics (Fluid Mosaic Model) with macro-level ecological adaptations (Allen's Rule).
The trap relies on the 'Quantitative Nuance' of surface area-to-volume ratios.
Students often memorize the association between Allen's Rule and cold climates but invert the geometric logic, confusing heat dissipation adaptations (large extremities, high SA:V ratio) with heat retention adaptations (short extremities, low SA:V ratio).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell – The Unit of Life - Class 11 |
| Concept | Plasma Membrane Fluidity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |