Cell membranes are said to be ________ because they allow some substances to pass but not others.
A) hydrophilic
B) a physical barrier
C) structural
D) selectively permeable
E) metabolically active

Question

Quizplus · Accepted Answer

Cell membranes are selectively permeable because they have specialized proteins and phospholipids that allow only certain molecules to pass through while preventing others from crossing the barrier. This selectivity is critical to maintaining the proper internal environment of the cell.

Cell Membranes Are Said to Be ________ Because They Allow