Answer:
1) B - protein channel
2) D - to assist in the movement of substances across the membrane by facilitated diffusion or active transport
Step-by-step explanation:
1) B is the answer because the proteins would travel through the protein channel to enter or leave the cell.
2) D is the answer because the channel allows protein molecules to pass through a selectively permeable cell membrane through active transport and facilitated diffusion.
Hope this helps!