Biochemistry instructors' perceptions of analogies and their classroom use

Biochemistry education relies heavily on students' abilities to conceptualize abstract cellular and molecular processes, mechanisms, and components. From a constructivist standpoint, students build their understandings of these abstract processes by connecting, expanding, or revising their prior conceptions and experiences. As such, biochemistry instructors often use analogies to teach difficult or hard-to-visualize topics to their classes by relating these target concepts to more commonplace analogs with which their students may already be familiar. For example, the binding of an enzyme to its substrate is often compared to a lock and a key; and ATP is frequently referred to as a cellular energy currency in discussions of metabolism and reaction coupling. Although the use of analogies in biochemistry classrooms is fairly common, the specific ways biochemistry instructors use analogies differ from instructor to instructor and class to class. In this article, we discuss biochemistry instructors' perceptions of the use of analogies in their classroom instruction. Specifically, we discuss (1) biochemistry instructors' objectives for using analogies, (2) their perceptions of the potential disadvantages associated with analogy use, (3) the sources of the analogies they use in their classes, and (4) the ways they perceive that analogies should be presented in class to promote student learning of biochemical concepts.