Incorporating Molecular Biophysics in the Undergraduate Curriculum

Abstract

The traditional introductory physics sequence doesn't work for life-science students. They don't find the traditional introductory topics - kinematics and Newton's laws to be relevant to their interests. That, combined with the well-known student misconceptions concerning describing motion mathematically, suggests that there's a need for a new starting point for the introductory physics sequence for life-science students. This presentation outlines a new active-learning approach that starts with the “marble game”, which simulates diffusion - a topic that students already know is fundamental to the life sciences. Students first learn how to play the game using a hands-on activity. They then implement the game in Excel producing a live graph of diffusion that leads them to discover that Fick's law of diffusion can be explained by unbiased random jumping between two boxes. In a guided-inquiry environment, students then apply the modeling techniques they learned from the marble game to drug elimination; radioactive decay; osmosis; ligand binding; enzyme kinetics; the Boltzmann factor; thermodynamics, phase equilibrium and entropy; random walks; membrane voltage, RC circuits and the action potential; models of the spread of COVID-19; Newtonian mechanics and biomechanics. The materials focus on engaging students in computational activities using kinetic Monte Carlo simulations and finite difference methods. These Excel activities allow them to discover for themselves the consequences and significance of model assumptions by reading and interpreting graphs, and by comparing model predictions with real data using linear regression and non-linear least-squares fits. A central theme of the materials is “thermodynamics from kinetics.” I've been successfully using this active-learning approach with undergraduate students for over 15 years. It provides a guided-inquiry environment that allows students to discover for themselves that science is an evidence-based endeavor with testable hypotheses that are supported by experiment. See http://circle4.com/biophysics for free textbook chapters and instructional videos.