Thai High School Students’ Understanding of Genes and Gene Expression

• In Event: Roundtable Session 37
  In Roundtable Session: Exploring the Role of Modeling in the Science Classroom

Abstract

A concept of the gene is a cornerstone concept in genetics. However, there is a growing concern among educators regarding students’ understanding of genetics in terms of the structural and functional nature of genes. Throughout the history of biological research, multiple scientific models of genes have been used to explain abstract and complex genetic phenomena. These multiple models of genes are also presented in the high school curriculum. A lack of acknowledgement of the existing multiple models of genes may influence students’ understanding of genetics. The purpose of this study is to explore Thai high school students' conceptions of genes and how students use the gene model to explain gene expression.
To explore common conceptions of genes among students, questionnaires were administered to 97 twelfth-grade Thai students from two classrooms of the public school after the instruction on genetics. Six participants were selected to participate in semi-structured interviews about how genes control genetic traits. Data on students’ conception of genes was analyzed based on the conceptual status of genes framework by Venville and Treagust (1998).
The results show that 72 students viewed genes as active particles and nine students viewed genes as passive particles. However, only ten students viewed genes as sequences of instructions, which the idea is important for understanding contents related to molecular genetics. Other responses could not be classified to these categories. The cross case analysis of the interviews revealed that students who viewed genes as sequences of instructions demonstrated efficient explanation regarding protein synthesis and gene expression. However, students who conceptualized genes as particles demonstrated considerable misunderstanding and had difficulty explaining how genes produce proteins to control traits.
Two main models of genes could be identified in high school genetics—the classical model and the molecular model. The classical model represents genes as particles in which genes determine genetic traits transferred from parents to offspring. The molecular model represents genes as sequences of instructions that are expressed to control structure and function of the cell. Findings indicate that with the current curriculum it is difficult for some students to understand the molecular model and to make connections between the classical model and the molecular model. Additionally, students could not apply appropriate models of genes in order to explain molecular genetic problems. Even though the problems concerning gene expression required the molecular model, most students still used the classical model.
The findings of this study suggest that there is a need to develop instructional strategies to facilitate students’ transition to a coherent view of the gene that incorporates both models and to enable students to use the appropriate model to explain genetic phenomena meaningfully in different contexts.

Author

• Nantaya Auckaraaree, University of Wisconsin - Madison