ABSTRACT
Biological membranes are complex and dynamic structures. The biological functions associated with membranes involve a number of different molecular species, and theories of how the molecular species are organized are still evolving. The “fluid mosaic” model of freely diffusing proteins and lipids in a two-dimensional fluid [1] has been refined to account for the presence of functional domains [2-4]. The composition, dynamics, source, and even existence of discrete segregated features, such as membrane “rafts,"are currently sources of significant controversy [5,6]. As a result of ambiguities in the complex nature of biomembranes, better physical and theoretical models are constantly under development.
