Chemical systems consisting only of elementary steps - a paradigma for nonlinear behavior

We present a new analytic method which allows one to interpret a mass-actio n kinetic reaction of arbitrary molecularity as the limit case of a sequenc e of bimolecular steps. Together with other technics (transformation of an arbitrary ODE into a polynomial ODE [8]; transformation of a polynomial ODE into a form which can be interpreted as a mass-action kinetic system [10]) , it is thus possible to construct an at most bimolecular mass-action kinet ic system with the same dynamic behavior as an arbitrary ODE. Furthermore, we demonstrate necessary improvements of the transformation given in [10]. Is is also shown that an arbitrary single mass-action kinetic reaction can be understood as a sequence of two reactions with a short-living intermedia te. In particular, it therefore follows that an autocatalytic reaction can always be approximated by two nonautocatalytic ones without changing the dy namics of the whole system.