| − | # {{sense|biology}} A series of intracellular [[chemical]] [[reactions]] ensuing from the association of a [[transmembrane protein]] with an [[extracellular]] signal, resulting in a subsequent alteration at the [[second messenger]] level and leading to a modification at the [[regulatory]] level. | + | # {{biochemistry}} A series of [[chemical]] [[reactions]] within a [[cell]] which start when a [[transmembrane protein]] comes into contact with a chemical signal, resulting in a [[second messenger]] being triggered. |
