What does it mean that biological membranes are permeable?

Question

What does it mean that biological membranes are permeable?

Answer 1

Liquids/Gases can pass through the membrane i.e. fluid exchange can occur

Answer 2

It means that things can go through. I'm not sure I quite understand your question, though... I can elaborate, though.

Membranes, biologically, are selectively permeable, meaning that only certain things can get by. This is extremely helpful in maintaining homeostasis (for example most things can't go through your skin, right? Imagine if they could! You swim in a pool with chlorine and the chlorine goes into your body! Imagine the havok that it would wreak) and very helpful in maintaining resting membrane potential.

Answer 3

that means that various substances can pass through them.a partially permeable membrane means it only allows certain substances to pass through whereas a fully permeable membrane allows each and every material to pass through it