Chemical barriers composed of phospholipid bilayers form within biological systems because
A) cells expend ATP to position the phospholipid tails close together.
B) hydrophobic exclusion results in the close positioning of the nonpolar tails.
C) van der Waals forces attract the polar heads to the water inside the cell.
D) the inability of the polar heads to dissolve in water causes the heads to adhere to one another.

Question

Quizplus · Accepted Answer

Phospholipid bilayers form because the hydrophobic (nonpolar) tails are excluded from water, leading them to position themselves away from water, while the hydrophilic (polar) heads face the aqueous environment.

Chemical Barriers Composed of Phospholipid Bilayers Form Within Biological Systems