Flowers Sharleen, Holder Kal H, Gardner Stephanie M
Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA.
J Microbiol Biol Educ. 2023 May 18;24(2). doi: 10.1128/jmbe.00221-22. eCollection 2023 Aug.
Understanding molecular processes and coordinating the various activities across levels of organization in biological systems is a complicated task, yet many curricular guidelines indicate that undergraduate students should master it. Employing mechanistic reasoning can facilitate describing and investigating biological phenomena. Biofilms are an important system in microbiology and biology education. However, few empirical studies have been conducted on student learning of biofilms or how students utilize mechanistic reasoning related to systems thinking to explain biofilm formation. Using mechanistic reasoning and the theory of knowledge integration as conceptual and analytical frameworks, we examined the features of 9 undergraduate biology students' mechanistic models of a specific transition point in biofilm development. From these data, we constructed a model of knowledge integration in the context of biofilms, which categorizes students' knowledge based on features of their descriptions (e.g., entities, correct connections, and the nature of connections). We found that 4 of 9 students produced a fragmented model, 4 of 9 students produced a transitional model, and 1 student produced a connected model. Overall, students often did not discuss cell-cell communication mechanics in their mechanistic models and rarely included the role of gene regulation. Most connections were considered nonnormative and lacked important entities, leading to an abundance of unspecified causal connections. We recommend increasing instructional support of mechanistic reasoning within systems (e.g., identifying entities across levels of organization and their relevant activities) and creating opportunities for students to grapple with their understanding of various biological concepts and to explore how processes interact and connect in a complex system.
理解分子过程并协调生物系统中不同组织层次的各种活动是一项复杂的任务，但许多课程指南表明本科生应该掌握这一技能。运用机制推理有助于描述和研究生物现象。生物膜是微生物学和生物学教育中的一个重要系统。然而，关于学生对生物膜的学习，或者学生如何运用与系统思维相关的机制推理来解释生物膜形成的实证研究很少。我们以机制推理和知识整合理论作为概念和分析框架，研究了9名本科生物学学生关于生物膜发育中一个特定转变点的机制模型的特征。基于这些数据，我们构建了一个生物膜背景下的知识整合模型，该模型根据学生描述的特征（如实体、正确的联系以及联系的性质）对学生的知识进行分类。我们发现，9名学生中有4名构建了碎片化模型，4名构建了过渡模型，1名构建了连贯模型。总体而言，学生在其机制模型中通常不讨论细胞间通讯机制，很少提及基因调控的作用。大多数联系被认为是非规范性的，且缺少重要实体，导致大量未明确的因果联系。我们建议增加对系统内机制推理的教学支持（例如，识别不同组织层次的实体及其相关活动），并为学生创造机会，让他们努力理解各种生物学概念，探索复杂系统中各过程如何相互作用和联系。
