Which molecule is least likely to cross a cellular membrane by simple diffusion?
A) Water
B) Oxygen
C) Nitrogen
D) Potassium ion
E) Carbon dioxide

Question

Quizplus · Accepted Answer

Potassium ion (K+) is least likely to cross a cellular membrane by simple diffusion due to its charge. Charged particles, such as ions, have difficulty passing through the hydrophobic core of the lipid bilayer without the assistance of specific transport proteins.

Which Molecule Is Least Likely to Cross a Cellular Membrane