signal transduction cell surface receptor signaling pathway GO:0007166 cell surface receptor linked signaling pathway cell surface receptor linked signal transduction biological_process A series of molecular signals initiated by activation of a receptor on the surface of a cell. The pathway begins with binding of an extracellular ligand to a cell surface receptor, or for receptors that signal in the absence of a ligand, by ligand-withdrawal or the activity of a constitutively active receptor. The pathway ends with regulation of a downstream cellular process, e.g. transcription. cell surface receptor linked signalling pathway