_______ are nonpolar macromolecules found in cell membranes; they prevent ions from freely entering cells.

Question

A.
carbohydrates

B.
nucleic acids

C.
proteins

D.
lipids

Answer 1

D. lipids

Lipids are nonpolar macromolecules found in cell membranes, and they help create a barrier that prevents ions and polar molecules from freely entering cells.