What is the function of channel proteins in cell membranes?

Channel proteins primarily function to allow solutes to cross the cell membrane passively. They create hydrophilic pathways through the lipid bilayer, enabling specific molecules, such as ions or water, to move across the membrane without the need for energy. This passive transport occurs along the concentration gradient, meaning substances move from areas of higher concentration to areas of lower concentration.

In contrast to other membrane proteins, such as carrier proteins that may require energy to transport larger molecules, channel proteins are selective and facilitate the free movement of smaller particles in response to concentration differences. This is crucial for maintaining cellular homeostasis, enabling cells to control their internal environment by regulating the flow of various ions and nutrients.

Understanding the role of channel proteins is fundamental when discussing cellular transport mechanisms and their implications for cell physiology and communication.