Question

question 20. the function of this protein is to... a. connect reproductive cells during fertilization b. exchange organelles or chromosomes between specialized cells c. strengthen the outer boundary of the cell d. allow certain substances to enter or leave the cell channel protein

Explanation:

Channel proteins in cell - membranes are integral membrane proteins that form channels to allow the passage of specific substances such as ions or small molecules across the cell membrane. They facilitate the movement of substances in and out of the cell.

Answer:

D. allow certain substances to enter or leave the cell