Abstract:
There are current concerns about genetically modified organisms, DNA fingerprinting, and cloning, all of which hinge on understanding genetics. Therefore, much attention has been given to research into the teaching and learning of genetics as it is a predominantly challenging topic for both teachers and students. This study used the triangulation convergence mixed methods design to explore Ghanaian SHS elective biology students’ conceptual understanding of chromosome, DNA and gene and to further develop and field test an instructional strategy to address students’ alternative conceptions and conceptual difficulties. A multistage sampling technique was used to select 96 SHS 3, 14 SHS2 elective biology students and 20 elective biology teachers. Three instruments, namely, achievement test, questionnaire and interviews were used to collect data. The data were analysed using percentages, charts, means, standard deviations, and themes. It was found that students had alternative conceptions (mainly in the categories of preconceived notions, factual misconceptions and conceptual misunderstandings) and other conceptual difficulties in learning the three basic genetics concepts. The use of conceptual change approach (Orientation-Discovery-Restructuring) helped students overcome their alternative conceptions and other conceptual difficulties. It was therefore, recommended that Biology teachers should use the conceptual change approach in teaching genetics.