why-do-semipermeable-membranes-allow-only-certain-molecules-to-pass-through

Question

Why do semipermeable membranes allow only certain molecules to pass through?

Accepted Answer

Because they are selective based on molecule size and charge.

Answer

Because they are impermeable to all molecules.

Answer

Because they allow all molecules to pass through.

Answer

Because they are only permeable to gases.