Date of this Version



mechanism, expert-novice, teaching, explanation, biology, modeling, science education


This document is intended for both instructors and students. Modified from the original MACH model this version, once cut and folded, creates a tetrahedral model that can conveniently be used as a teaching and learning tool to inform and guide students on how to write expert quality explanations of biological mechanisms. Each vertex of the tetrahedron represents a component of the model namely, Methods, Analogy, Context, and How. For a coherent and complete explanation about molecular mechanisms, it is important to integrate information pertaining to all four components of the model. The tetrahedral MACH model has been tested in both undergraduate biology and biochemistry courses and is recommended for use by both practitioners and students in the life sciences. Details of its use as a classroom activity can be found in the Purdue International Biology Education Research Group (PIBERG) ePubs collection. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.