The relative impermeability of membranes to water-soluble molecules is a result of the ____.
A) nonpolar nature of water
B) presence of large proteins that extend through both sides of membranes
C) presence of inorganic salt crystals scattered through some membranes
D) presence of cellulose and waxes
E) presence of phospholipids in the lipid bilayer

Question

Quizplus · Accepted Answer

The presence of phospholipids in the lipid bilayer is responsible for the relative impermeability of membranes to water-soluble molecules. The hydrophobic tails of phospholipids repel water and water-soluble molecules, preventing their easy passage through the membrane.

The Relative Impermeability of Membranes to Water-Soluble Molecules Is a Result