The part of the plasma membrane that is in contact with the external environment of the cell consists of
A)hydrophobic portions of the constituent molecules.
B)hydrophilic portions of the constituent molecules.
C)neutral (uncharged) molecules.
D)nonpolar ends of the constituent molecules.

Question

Quizplus · Accepted Answer

The hydrophilic portions of the constituent molecules in the plasma membrane, such as the phospholipid head groups and membrane proteins, face the external environment of the cell, which is typically aqueous in nature. This allows for interactions with water and other polar molecules outside the cell. The hydrophobic portions of the membrane face toward the interior of the cell, away from the external environment.

The Part of the Plasma Membrane That Is in Contact