How Do Cells Communicate?
Another class of membrane proteins that aid in cellular communication are channel proteins. These proteins act as molecular gates that allow the passage of small molecules and ions, for example, glucose and sodium, across the membrane in response to a stimulus, such as an electrical current in the case of ions or insulin signaling in the case of glucose.
At any point in time, an individual cell may be receiving messages from multiple receptors or channel proteins. Ultimately, the fate of the cell depends on the combination of signals it receives and the resulting decisions it makes.