Using Variation Theory To Enhance Students Capability In Solving Pedigree Problems

This dissertation, "Using Variation Theory to Enhance Students' Capability in Solving Pedigree Problems" by Tat-ho, Lam, 林達豪, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: This thesis reports on a learning study that employed variation theory to enhance a domain-specific generic-capability pedigree analysis of Hong Kong secondary five students so as to help them develop their capability to solve pedigree problems. Pedigree analysis is a study of inheritance in genetics, which includes the deduction of dominant and recessive characters. The literature and local examination reports suggested that solving pedigree problems is difficult for students, as the process of deduction demands conceptual understanding and use of scientific language. Three biology teachers participated in this learning study using variation theory. Teachers shifted the focus of lesson observation from teaching performance to student learning, to how students deduced the dominant character from pedigree problems, which was the object of learning. To explore the effectiveness of such teaching and learning to solve pedigree problems through different patterns of variation, two cycles of learning study were conducted in two senior biology classes. Results showed that students were more able to deduce the dominant character with relevant genetic principles by experiencing the variations. Both conceptual understanding and scientific language are critical aspects of solving pedigree problems. This study also suggests that explanatory scientific writing needs to be broken down into different components and then differentiated patterns of variation designed to let students discern those components and their relationships; in that way their writing can be 'scaffolded' in a stepwise manner rather than giving them the whole writing framework at once. However, the identification of critical features and patterns of variation and their relevance to the object of learning should be considered carefully and explored further. DOI: 10.5353/th_b5387974 Subjects: Study and teaching (Secondary) - Genetics - China - Hong Kong