The behavior of a cell often relies on the chemical signals it is exposed to in its environment. In general, two types of chemical signals can be found floating through the cellular environment: water-soluble (hydrophilic) molecules or fat-soluble (hydrophobic) molecules. Both are important components of cellular communication and physically interact with cellular structures to facilitate this function. In virtually every case, the cellular structures that these chemical signals interact with are receptor proteins. Receptors and the Surface of a Cell A cell is surrounded by a membrane, which forms a barrier between the inside and outside of the cell. This…