Channel protein have gate that opens and close which allow the passage of polar substance or ions to move to permeable membrane of the cell by diffusion. They are water filled and allow the movementof charged molecules inside and outside the cell membrane i.e polar molecules move through non polar bilayer of the cell membrane.
I can’t see the image but I would guess animals such as deer or horse or elephants or any large animal have the ability to run over the rocks and turn them to smaller sediments
