The modelling of a primitive 'sustainable' conservative cell

The simple sustainable or 'eternal' cell model, assuming preservation of al l proteins, is designed as a building block, a primitive element upon which one can build more complete functional cell models of various types, repre senting various species. In the modelling we emphasize the electrophysiolog ical aspects, in part because these are a well-developed component of cell models and because membrane potentials and their fluctuations have been gen erally omitted from metabolically oriented cell models in the past. Fluctua tions in membrane potential deserve heightened consideration because probab ly all cells have negative intracellular potentials and most cells demonstr ate electrical activity with vesicular extrusion, receptor occupancy, as we ll as with stimulated excitation resulting in regenerative depolarization. The emphasis is on the balances of mass, charge, and of chemical species wh ile accounting for substrate uptake, metabolism and metabolite loss from th e cell. By starting with a primitive representation we emphasize the conser vation ideas. As more advanced models are generated they must adhere to the same basic principles as are required for the most primitive incomplete mo del.