Question

which type of material can easily pass through a cell membrane without the assistance of a protein?
o ions
o charged molecules
o large molecules
o none of the above

Explanation:

Cell membranes are composed of a lipid - bilayer. Ions, charged molecules, and large molecules cannot easily pass through the non - polar lipid - bilayer without the assistance of proteins (channels or carriers). The lipid - bilayer is non - polar and repels charged and large substances.

Answer:

None of the above