THE USE OF A HANDS-ON MODEL IN LEARNING THE REGULATION OF AN INDUCIBLE OPERON AND THE DEVELOPMENT OF A GENE REGULATION CONCEPT INVENTORY

Abstract

A central concept in genetics is the regulation of gene expression. Inducible gene expression is often taught in undergraduate biology courses using the lac operon of Escherichia coli (E. coli). With national calls for reform in undergraduate biology education and a body of literature that supports the use of active learning techniques including hands-on learning and analogies we were motivated to develop a hands-on analogous model of the lac operon. The model was developed over two iterations and was administered to genetics students. To determine the model’s worth as a learning tool a concept inventory (CI) was developed using rigorous protocols. Concept inventories are valuable tools which can be used to assess students’ understanding of a topic and pinpoint commonly held misconceptions as well as the value of educational tools. Through in-class testing (n =115) the lac operon concept inventory (LOCI) was demonstrated to be valid, predictive, and reliable (α coefficient = 0.994). LOCI scores for students who participated in the hands-on activity (n = 67) were 7.5% higher (t = -2.281, P < 0.05) than students who did not (n = 62). Use of the model is also supported by student feedback from two surveys. This study provides an effective activity that aids students’ understanding of the lac operon. We were able to determine the efficacy of the activity and identify misconceptions held by students about the lac operon because of the use of a valid and reliable CI.