Question

Which of the following factors does not affect membrane permeability?

• Temperature
• The saturation of hydrocarbon tails in membrane phospholipids
• The amount of cholesterol in the membrane
• The polarity of membrane phospholipids

 

Answer 1

The correct answer is option (4) the polarity of membrane phospholipids because usually, the phospholipids have hydrophobic and hydrophilic regions, so the polarity of phospholipids do not change the permeability.

The main factors that affect the permeability of membrane are:

• Temperature: increasing temperature leads to increasing permeability
• Saturation of fatty acids: more saturated fatty acids less fluidity, whereas the more unsaturated fatty acids more fluidity.
• % of cholesterol: more cholesterol in the membrane increases packing and leads to reduce fluidity.