ABSTRACT
Action spectroscopy is a general approach toward identifying the receptor pigment(s) for a particular photobiologicalresponseore¨ect.§eearlyidenti©cationofmajorchromophores,suchasrhodopsin andchlorophyll,dependedoncomparisonoftheactionspectraforvisionandphotosynthesis,respectively, with the absorption spectra of candidate pigments.
