No Arabic abstract
In an Introductory Physics for Life Science (IPLS) course that leverages authentic biological examples, student ideas about entropy as disorder or chaos come into contact with their ideas about the spontaneous formation of organized biological structure. It is possible to reconcile the natural tendency to disorder with the organized clustering of macromolecules, but doing so in a way that will be meaningful to students requires that we take seriously the ideas about entropy and spontaneity that students bring to IPLS courses from their prior experiences in biology and chemistry. We draw on case study interviews to argue that an approach that emphasizes the interplay of energy and entropy in determining spontaneity (one that involves a central role for free energy) is one that draws on students resources from biology and chemistry in particularly effective ways. We see the positioning of entropic arguments alongside energetic arguments in the determination of spontaneity as an important step toward making our life science students biology, chemistry, and physics experiences more coherent.
Energy is a complex idea that cuts across scientific disciplines. For life science students, an approach to energy that incorporates chemical bonds and chemical reactions is better equipped to meet the needs of life sciences students than a traditional introductory physics approach that focuses primarily on mechanical energy. We present a curricular sequence, or thread, designed to build up students understanding of chemical energy in an introductory physics course for the life sciences. This thread is designed to connect ideas about energy from physics, biology, and chemistry. We describe the kinds of connections among energetic concepts that we intended to develop to build interdisciplinary coherence, and present some examples of curriculum materials and student data that illustrate our approach.
A goal of Introductory Physics for Life Sciences (IPLS) curricula is to prepare students to effectively use physical models and quantitative reasoning in biological and medical settings. To assess whether this goal is being met, we conducted a longitudinal study of the impact of IPLS on student work in later biology and chemistry courses. We report here on one part of that study, a comparison of written responses by students with different physics backgrounds on a diffusion task administered in a senior biology capstone course. We observed differences in student reasoning that were associated with prior or concurrent enrollment in IPLS. In particular, we found that IPLS students were more likely than non-IPLS students to reason quantitatively and mechanistically about diffusive phenomena, and to successfully coordinate between multiple representations of diffusive processes, even up to two years after taking the IPLS course. Finally, we describe methodological challenges encountered in both this task and other tasks used in our longitudinal study.
An important goal of introductory physics for the life sciences (IPLS) is for those students to be prepared to use physics to model and analyze biological situations in their future studies and careers. Here we report our findings on life science students ability to carry out a sophisticated biological modeling task at the end of first-semester introductory physics, some in a standard course (N = 34), and some in an IPLS course (N = 61), both taught with active learning and covering the same core physics concepts. We found that the IPLS students were dramatically more successful at building a model combining multiple ideas they had not previously seen combined, and at making complex decisions about how to apply an equation to a particular physical situation, although both groups displayed similar success at solving simpler problems. Both groups identified and applied simple models that they had previously used in very similar contexts, and executed calculations, at statistically indistinguishable rates. Further study is needed to determine whether IPLS students are more expert problem-solvers in general or solely in biological settings.
As part of a larger research project into massively open online courses (MOOCs), we have investigated student background, as well as student participation in a physics MOOC with a laboratory component. Students completed a demographic survey and the Force and Motion Conceptual Evaluation at the beginning of the course. While the course is still actively running, we have tracked student participation over the first five weeks of the eleven-week course.
Proficiency with calculating, reporting, and understanding measurement uncertainty is a nationally recognized learning outcome for undergraduate physics lab courses. The Physics Measurement Questionnaire (PMQ) is a research-based assessment tool that measures such understanding. The PMQ was designed to characterize student reasoning into point or set paradigms, where the set paradigm is more aligned with expert reasoning. We analyzed over 500 student open-ended responses collected at the beginning and the end of a traditional introductory lab course at the University of Colorado Boulder. We discuss changes in students understanding over a semester by analyzing pre-post shifts in student responses regarding data collection, data analysis, and data comparison.