Question

which molecule would most easily pass through the cell membrane by diffusion? a protein b chloride ion c glucose d oxygen

Explanation:

Cell membranes are composed of a lipid - bilayer. Small, non - polar molecules can easily diffuse through the lipid - bilayer. Oxygen is a small, non - polar molecule. Proteins are large macromolecules. Chloride ions are charged and cannot easily cross the non - polar lipid interior of the membrane. Glucose is a relatively large polar molecule and requires transport proteins for efficient movement across the membrane.

Answer:

D. Oxygen