The initial state of a growth process system

For microbial growth process systems die simplest initial state consists of an aqueous solution of the necessary inorganic macro- and micronutrients, vitamins, and a single organic substance, or substrate, that serves both as a carbon source and an electron donor. The macro- and micronutrients are those required by all cells. These are NH faq) or NOj(aq), H2P04(aq), SC (aq), K (aq), Mg (aq), and Ca Xaq)as macronutrients, and HjBOjfaq), Cu (a l) Cl (aq), Fe X l)  

Animal cell culture systems all require at least two substrates as carbon and/or nitrogen sources, and electron donors [1] and usually require more [2], as illustrated by reference [3]. Higher plant cell culture systems are equally complex [4]. This complicates efforts to understand what is the source of energy that enters into 

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