因果机制推理是一种思维策略,可以帮助学生使用单独的本科课程中通常强调的核心思想来解释复杂的现象,因为它要求学生识别底层实体,解压缩它们的相关属性和相互作用,并将它们链接到构造机械解释。作为一个跨学科的生物学家团体,化学家,和教师教育工作者,我们设计了一组支架任务,这些任务需要来自生物学和化学的内容知识来构建跨越三个尺度的嵌套分层机制解释(分子,大分子,和细胞)。我们检查了七门入门和高级生物学和化学课程中的学生解释,以确定机械解释的构建如何在课程中变化以及不同规模的机械解释的构建之间的关系。我们发现非,局部,并在所有课程和每个量表上完成机械解释。完整的机械解释构造在介绍性化学中最低,在生物学和有机化学中也是如此,生物化学最高。跨任务,在较小的尺度上构造机械解释与在较大的尺度上构造机械解释有关;然而,分子尺度学科资源的使用仅与大分子的完整机械解释有关,不是细胞尺度。
Causal mechanistic reasoning is a thinking strategy that can help students explain complex phenomena using core ideas commonly emphasized in separate undergraduate courses, as it requires students to identify underlying entities, unpack their relevant properties and interactions, and link them to construct mechanistic explanations. As a crossdisciplinary group of biologists, chemists, and teacher educators, we designed a scaffolded set of tasks that require content knowledge from
biology and chemistry to construct nested hierarchical mechanistic explanations that span three scales (molecular, macromolecular, and cellular). We examined student explanations across seven introductory and upper-level
biology and chemistry courses to determine how the construction of mechanistic explanations varied across courses and the relationship between the construction of mechanistic explanations at different scales. We found non-, partial, and complete mechanistic explanations in all courses and at each scale. Complete mechanistic explanation construction was lowest in introductory chemistry, about the same across
biology and organic chemistry, and highest in biochemistry. Across tasks, the construction of a mechanistic explanation at a smaller scale was associated with constructing a mechanistic explanation for larger scales; however, the use of molecular scale disciplinary resources was only associated with complete mechanistic explanations at the macromolecular, not cellular scale.