UPPER SECONDARY SCHOOL STUDENTS' CONCEPTUAL UNDERSTANDING OF BIOLOGICAL CORE CONCEPTS

People need to be capable of making biologically justified decisions in their everyday life, especially regarding their health, e.g. vaccination, diet or medical treatment. This emphasises the need of biological basic knowledge and understanding of topics for all people to be able of using these competences to solve everyday problems and make justified decisions. Students should conceptually understand the biological core topics and its core concepts as this enhances the development of higher-level abilities enabling students to apply their learning. But there are few studies researching the assessment of students' conceptual understanding of core topics taught in school biology. The aim of this study is to determine the upper secondary school graduates' achievement profiles of biological conceptual understanding of core topics by means of latent profile analysis (LPA) and detect the differentiating the difficulties of biological core topics. Sample of this research consisted of 215 (162 females and 53 males) upper secondary school graduates. They undertook the paper-and-pencil test in July 2019. The biology test consisted of 50 multiple-choice questions and students were given 120 minutes to complete the test. Three experts evaluated the accordance of the test items with the biology curriculum and with specified learning outcomes. Test results showed that the most difficult items belonged to the 3rd core topic "Inheritance and variation traits". Only 34 % of the students' answers were correct. The best percentage of correct answers (49 %) was gained within the items about evolution.