The Calculus of Looping Sequences for Modeling Biological Membranes

1 Introduction Cell biology, the study of the morphological and functional organization of cells,is now an established field in biochemical research. Computer Science can help the research in cell biology in several ways. For instance, it can provide biolo-gists with models and formalisms capable of describing and analyzing complex systems such as cells. In the last few years many formalisms originally developedby computer scientists to model systems of interacting components have been applied to Biology. Among these, there are Petri Nets [16], Hybrid Systems [1],and the ss-calculus [9, 25]. Moreover, new formalisms have been defined for de-scribing biomolecular and membrane interactions [2, 7, 8, 11, 21, 23]. Others, suc