Question

The fluidity of membranes in a plant in cold weather may be maintained by

• A. increasing the number of phospholipids unsaturated hydrocarbon tails
• B. increasing the proportion of intergral proteins
• C. increasing concentration of cholesterol in membrane
• D. increasing the number of phospholipids with saturated hydrocarbon tails

Answer 1

Answer: (A), (C)

increasing concentration of cholesterol in membrane

Unsaturated hydrocarbon fatty acid tails result in more space between the phospholipids. More space between the phospholipids results in more fluidity.
The presence of cholesterol in between phospholipids in cold temperatures leads to more fluidity. And the presence of cholesterol in between phospholipids at higher temperatures leads to lesser fluidity.