Using physics simulation to understand the biology process of ion channels

Abstract This work presents a pedagogical proposal that employs the Circuit Construction Kit: DC computer simulation from the PhET platform to address Millman’s theorem and facilitate the understanding of the principles involved in the electrical equilibrium of biological cells. The study models the cell membrane potential as a simplified electrical circuit, considering ion channels (Na + , K + , and Cl − ) as resistors and concentration gradients as voltage sources. Through simulation, the effects of varying ionic conductances on the resting potential are analysed, highlighting how the inactivation of the Cl − channel or changes in the conductances of Na + and K + , aimed at restoring equilibrium, affect cellular homeostasis and excitability. We argue that the proposed approach promotes intuitive learning by reducing reliance on mathematical formalism and encouraging the application of physical concepts to real physiological contexts. The simulation has proven to be an effective teaching tool in health-related courses, fostering virtual experimentation and the qualitative interpretation of complex phenomena.