[Campbell Biology P.178] Membrane fluidity is crucial for proper cellular function. Which of... | Practice Question

Membrane fluidity is crucial for proper cellular function. Which of the following statements accurately describes the evolutionary adaptations related to membrane fluidity in response to environmental temperatures?

  • A: Organisms in extremely cold environments, like fish, typically decrease the proportion of unsaturated hydrocarbon tails in their membrane lipids to maintain fluidity.
  • B: In response to varying temperatures, organisms generally maintain a constant lipid composition in their membranes to ensure stable fluidity.
  • C: Bacteria and archaea thriving in thermal hot springs often have unusual lipids that prevent excessive fluidity at high temperatures.
  • D: Winter wheat increases the percentage of saturated phospholipids in autumn to prevent membrane solidification during winter.

Explanation

The text states that 'some bacteria and archaea thrive at temperatures greater than 90°C 194°F in thermal hot springs and geysers. Their membranes include unusual lipids that may prevent excessive fluidity at such high temperatures.' This directly supports option C. Other options misrepresent the adaptations described.