Question

The membrane which allows all substances to pass through it.​

Answer 1

Answer:

Plasma membrane or cell membrane

Answer 2

Answer:

i think  [cell membrane]

Explanation:

Simple Diffusion across the Cell (Plasma) Membrane. The structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.