1. A method of identifying an operational reaction pathway of a biosystem, wherein the steps of said method are performed on a suitably programmed computer programmed to execute the steps comprising: (a) providing a set of systemic reaction pathways through a reaction network representing said biosystem; (b) providing a set of phenomenological reaction pathways of said biosystem; (c) comparing said set of systemic reaction pathways with said set of phenomenological reaction pathways; and (d) providing an output to a user of the selection of a pathway common to said set of systemic reaction pathways and said phenomenological reaction pathways of said biosystem, wherein said pathway common to said sets is an operational reaction pathway of said biosystem.