Control of flux through a metabolic pathway requires that
*The degree to which metabolic steps determine the metabolic flux varies based on the organisms' metabolic needs.
*The change in flux that occurs due to the above requirement being communicated to the rest of the metabolic pathway in order to maintain a steady-state.
Control of flux in a metabolic pathways:
*The control of flux is a systemic property, that is it depends, to varying degrees, on all interactions in the system. 
*The control of flux is measured by the flux control coefficient
*In a linear chain of reactions, the flux control coefficient will have values between zero and one.
*A step with a flux control coefficient of zero means that, that particular step, has no influence over the steady-state flux. 
*A step in a linear chain with a flux control coefficient of one means that that particular step has complete control over the steady-state flux. 
*A flux control coefficient can only be measured in the intact system and cannot for example be determined by inspection of an isolated enzyme in vitro.