A computer model based on a previous model for aerobic growth of Escherichia coli is described which simulates cell composition, size, and shape; length of C and D periods; cell yields; and the rate of product formation of anaerobically grown cells of E. coli B/r-A on glucose-limited minimal medium. To verify the simulation results, the values of cell volume, cell content of DNA, RNA, and protein, substrate yield, ATP yield, and fermentation products for various growth rates were obtained experimentally. Model predictions are in good agreement with experimental results. Such agreement supports a hypothesis that only those equations describing energy metabolism need to be modified and other cell functions are not grossly altered by a switch from aerobic to an aerobic growth. The model's ability to predict reasonable growth responses under anaerobic conditions by only modifying energy metabolism is a further indication of the robust nature of the description of cell physiology included in the development of the aerobic model.