Creating 3D physical models to probe student understanding of macromolecular structure.

The high degree of complexity of macromolecular structure is extremely difficult for students to process. Students struggle to translate the simplified two-dimensional representations commonly used in biochemistry instruction to three-dimensional aspects crucial in understanding structure-property relationships. We designed four different physical models to address student understanding of electrostatics and noncovalent interactions and their relationship to macromolecular structure. In this study, we have tested these models in classroom settings to determine if these models are effective in engaging students at an appropriate level of difficulty and focusing student attention on the principles of electrostatic attractions. This article describes how to create these unique models for four targeted areas related to macromolecular structure: protein secondary structure, protein tertiary structure, membrane protein solubility, and DNA structure. We also provide evidence that merits their use in classroom settings based on the analysis of assembled models and a behavioral assessment of students enrolled in an introductory biochemistry course. By providing students with three-dimensional models that can be physically manipulated, barriers to understanding representations of these complex structures can be lowered and the focus shifted to addressing the foundational concepts behind these properties.