Evaluation of molecular visualization software for teaching protein structure - Differing outcomes from lecture and lab

In this study we measured the learning outcomes resulting from using molecular visualization software in lecture and in the teaching laboratory of a large introductory-level undergraduate biology majors' course. The study was initially carried out in the Fall semester of 1999; the results of this study were used to devise an expanded laboratory component that was evaluated in a second study carried out in the Fall of 2000. In both studies, students (n = 175 and 161) attended two 50-min lectures that used molecular visualization software to explain protein structure and function and the gene-protein connection. Students also used this software during one 3-h laboratory session as a tool for exploring these topics. Students completed open-ended pre- and post-surveys that involved a related but unfamiliar task. Survey responses were scored for correctness, as well as by the type(s) of explanations used in the response. We found the following eight types of responses that students employed to explain protein structure and function: genetics, protein structure, chemical interactions, amino acid sequence, purpose/teleology, extrinsic factors, miscellaneous, and none. In both studies, the frequencies of correct answers, as well as the frequencies of each response type, showed significant changes as a result of lecture and/or lab. The effects of lecture were highly similar in both studies. The changes in the expanded lab resulted in significant changes in outcome. Overall, the curriculum effectively communicated several core concepts in protein biochemistry and expanded the conceptual toolkit that students applied to problems of protein structure and function. Lecture increased students' understanding of the role of amino acid sequence, whereas lab tended to increase their understanding of three-dimensional structure and the gene-protein connection. Our results demonstrate that exposure to molecular visualization, even for a relatively brief time, can improve students' understanding of protein structure and function. In addition, we demonstrate the differing and largely non-overlapping effects of lecture and lab, suggesting that effective use of molecular visualization should involve both types of activities.