Question

The cell membrane is a highly selective barrier that controls the movement of substances in and out of the cell. In fact, polar molecules are unable to go across unless A. they are broken down into smaller pieces. B. they are enclosed in water-filled vesicles. C. they pass through channels in the cell membrane. D. they react with other substances to become nonpolar.

Answer 1

Im going to have to go with C. they pass through channels in the cell membrane

Answer 2

C. They pass through channels in the cell membrane.

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