The use of physical models of protein structures to probe for learning and reasoning difficulties (618.20)

Abstract

Biochemistry educators make extensive use of external representations (ERs) to help students visualize the submicroscopic world of biochemical structures, including proteins. Despite broad acceptance, little is understood about the effectiveness of ERs for promoting student learning about protein structure. In this study, we investigate the effectiveness of a physical model kit, Protein Folder, and a protein structure chart, The Protein Chart, at probing for student understanding of protein structure. Twenty‐six students, enrolled in a biochemistry course, participated in a two‐week unit, which made use of the ERs to teach about protein structure. To investigate the educational effectiveness of the ERs, we identified student difficulties resulting from worksheets, quizzes, tests and interviews. We classified difficulties using the conceptual‐reasoning‐mode (CRM) model. This work revealed four novel difficulties students encounter when learning about protein structure. We found that students have difficulties making distinctions between the linear sequence of a protein and its spatial sequence, building protein structures that reflect standard amino acid chirality, portraying correct spatial separation between amino acids in a protein model, and correctly orienting protein strands within a chain. Identification of these difficulties allows educators to anticipate obstacles their student can face and may lead to eventual improvements in the use of ERs for teaching about protein structure.