Question

The crossing of the ions from the plasma membrane via simple diffusion can be prevented by

• A. Ions that are too large
• B. Ions that carries charge
• C. Ions that are hydrophobic
• D. Ions that do not produce a concentration difference
• E. Ions that cannot interact with membrane-bound proteins

Answer 1

The correct option is B Ions that carries charge

Plasma membrane is composed of amphoteric proteins and a bilayer lipid having polar heads arranged towards the outer surface with unexposed hydrophobic tail in the inner region. The charged molecules repel the uncharged one and disturb the potential of the membrane while the non-polar molecules maintain a constant potential. So, the polar molecules are unable to diffuse out of the plasma membrane while, the non-polar molecules can easily pass out of it.
So, the correct answer is option B.