Suppose you are given a diffusion bag that is permeable to both water and a protein. You fill the diffusion bag such that it contains 99% water and 1% protein. You place the diffusion bag into a beaker filled with 98% water and 2% protein. Predict what will happen next.

Protein moves outside while water moves inside.

Explanation:

Protein diffuses inside the bag whereas water moves outside the bag because the amount of protein is lower inside the bag and water is lower in concentration outside the bag so to equalize the concentration of the protein and water the diffusion of both protein and water occurs. If the bag is not permeable then the exchange of water and protein did not held so for achieving equilibrium diffusion occurs.