Abstract. In many chemical and biological applications, systems of differential equations containing unknown parameters are used to explain empirical observations and experimental data. 1. Introduction. The empirical study of many current biological problems generates large and complex data sets. How best to use this data to generate and improve scientific hypotheses is a subject of great interest to biologists, mathematicians, statisticians, and computational scientists. Combining these various scientific and quantitative disciplines requires careful communication. Figure 1 illustrates the flow of information for a typical problem in quantitative biology.The modeling process described in the present work began with the formation of a scientific hypothesis based on laboratory experiments and intuition. This theory was used by biochemists to construct an experimental protocol and generate data. The same theory was used by mathematicians to develop a mathematical model, which was studied analytically and simulated computationally. Both models were intended to confirm or improve hypotheses. The theory and experiments are described in section 2, while the mathematical and computational models are described in sections 3 and 4, respectively.For the biological model to feed back on theory, its output data needed to be analyzed. For the quantitative model to feed back on theory, its unknown parameter