Final answer:
Membrane pores in cell membranes play the role of facilitating the movement of ions.
Step-by-step explanation:
The most likely role of membrane pores in cell membranes is to facilitate the movement of ions. Membrane pores, also known as channel proteins, act like pores in the membrane that allow specific substances, such as ions, to pass through. These channel proteins help maintain the balance of salts, nutrients, and proteins within the cell, thus supporting its normal functioning. It is important to note that different types of channel proteins exist, including water channel proteins known as aquaporins, which allow the rapid diffusion of water across the membrane.