Though originally developed for chemical kinetics, this approach has found applications in other domains, including biology, and has even been applied to obtain macro-level insights into the metabolism of complete living systems. Criticisms about considering the Arrhenius equation as more than an empirical tool have warned against its overuse and overinterpretation. Particularly relevant are criticisms related to the use of the Arrhenius model to study microbial growth, which is often used as a proxy for metabolic activity measurements via the Monod model. Specific criticisms include temperature limitations, complex biological interactions, phase transitions, metabolic shifts, and adaption over long periods. While other temperature-dependant biological equations exist, including those that modify the Arrhenius equation to account for the non-linear relationship in plots of ln(k) versus 1/T, the original approach can yield important insights when applied "reasonably", for example, over a range of physiological temperatures where the slope is linear and single valued. Moreover, direct measurements of metabolic activity, for example, via current produced by an EAB, can probe the metabolic activity of the organism in its current state, before it can grow or adapt to long-term changes in experimental conditions.