Question

How can you prove that bark cells are impervious to gases and water?

Answer 1

well there is no experiment to prove that bark cells are impervious to gases and water.
But they are mostly impervious to water and gases due to deposition of a material called suberin.Also,if the two barks placed in water and air neither swell nor shrink.this also proves
that bark cells are impervious to gases and water.
hope this will help...