Question

1. the diagram below shows a section of a cell membrane that includes a channel protein. the function of this protein is to

strengthen the outer boundary of the cell
connect reproductive cells during fertilization
allow certain substances to enter or leave the cell

Explanation:

Channel proteins in cell - membranes are selective pores. They facilitate the passive transport of specific ions or molecules across the cell membrane, allowing certain substances to enter or leave the cell. They do not strengthen the cell boundary (that's the role of structural components like the cell wall in some cells or the lipid - bilayer's integrity), nor do they connect reproductive cells during fertilization.

Answer:

Allow certain substances to enter or leave the cell