obvious properties, its structure, composition, electrical properties, me chanical properties, and most particularly, its permeability properties. None of these properties are obviously associated with surface enzymes. What are the functions of the cell surface that may require the presence of enzymes? From a purely hypothetical point of view, the cellular activities in which cell surface enzymes are potentially functional can be divided into two categories; first, those activities related to the production and maintenance of the cell surface structure itself, and second, those activities...