There has been a dramatic surge in the number of physicists working on biological problems during the past decade. However, physicists' quantitative, deductive way of thinking has not had much traction when confronted with the vast complexity underlying biological systems. One measure of this complexity is the large number of biochemical parameters necessary to describe even systems comprising of a few components. In this talk, I will show how a simple phenomenological approach in the spirit of thermodynamics can provide quantitative, predictive understanding of the physiological behaviors of bacterial cells. I will present a number of linear relations (analogous to Ohm's law) describing the allocation of cellular resources for exponentially growing bacteria cells. With a single phenomenological parameter, these growth laws can accurately predict the response of bacteria to various perturbations, including the fitness effect of protein over-expression and the abrupt response of bacteria to the application of antibiotic drugs.