The Role of Domain-Specific Knowledge in Generative Reasoning About Complicated Multileveled Phenomena

Promoting the ability to reason generatively about novel phenomena and problems students may encounter in their everyday lives is a major goal of science education. This goal proves to be a formidable challenge in domains, such as molecular genetics, for which the accumulated scientific understandings are daunting in both amount and complexity. To develop effective instruction that fosters generative reasoning we need to have a sound understanding of the types of knowledge in the domain that are critical for such reasoning. In this study I examined the ensemble of knowledge, both general and domain-specific, undergraduate students employed in reasoning about problems in genetics. I found that students initially formulate a solution in terms that are not domain specific and that serve as a frame–solution frame–that outlines and constrains a more specific and domain-appropriate explanation. This solution frame is then filled in with two powerful forms of domain-specific knowledge I term: domain-specific heuristics and domain-specific explanatory schemas. These knowledge forms embody understandings of central mechanisms and entities in molecular genetics. By invoking these domain-specific knowledge forms, students were able to reason about a variety of both familiar and novel genetics problems. I present a cognitive model that highlights the role of these powerful conceptual understandings in promoting generative reasoning in genetics.