What adaptation would you expect to see in the cell membranes of organisms living in extremely cold environments?

Understand the Problem

The question is asking about the adaptations in cell membranes of organisms living in extremely cold environments. Specifically, it's asking about how the lipid composition of the cell membrane would change to maintain fluidity at low temperatures. The options relate to cholesterol content, integral protein concentration, and the saturation of fatty acids.

More Information

Unsaturated phospholipids have kinks in their structure, preventing them from packing as tightly together as saturated phospholipids. Shorter fatty acid tails also contribute to increased fluidity, as they have weaker interactions with each other.

Tips

A common mistake is to assume that cold environments would lead to more saturated fats in the membrane, thinking it would 'solidify' the membrane for protection. However, fluidity is essential for membrane function, even in the cold.

Sources

• Organisms can be found living in extreme temperature conditions both in extreme cold or extreme heat. What types of differences would you expect to see in the lipid composition of organisms that live at these extremes. - homework.study.com
• Cold Temperature Adaptation and Growth of Microorganisms † - pubmed.ncbi.nlm.nih.gov
• [DOC] Cold water adaptations of various animals - usna.edu