The effectiveness and problems of utilizing diagrams for secondary school students' learning of cell divisions

Abstract

Cell division is a topic widely recognized by biology teachers for its importance in the curriculum. However, it is also regarded by teachers and students as a very difficult topic. Students at different school levels often hold many misconceptions in cell divisions. While diagrams have been so commonly employed in biology textbooks to enhance the textual representation of cell divisions, the researcher of this study questioned about the cognitive role of the diagrams in helping students construct new concepts of cell divisions, as well as students’ competence in learning from the diagrams.

This exploratory study was conducted to investigate how secondary school students made use of textbook diagrams to gain new information about cell divisions, if and how the diagrams induced misconceptions in students, the problems students encountered when interpreting the diagrams and captions, and their perceptions of the usefulness of diagrams in learning cell divisions specifically and biology in general.

Twenty-two secondary four students took part in this study. They were provided with a textbook illustration of mitotic and meiotic cell divisions, consisting of schematic diagrams and captions, for self-study. Data was collected from the students’ performance on a task sheet and their responses in individual interview. The task sheet assessed the new concepts (and/or misconceptions) constructed by the students through their (mis-)interpretation of the diagrams and captions in the illustration. The individual interview probed deeper into the students’ cognitive processing of the information in the illustration.

Results showed that the students were able to employ different strategies to interpret the diagrams and captions to construct new knowledge to solve problems in the task sheet. However, they also showed weaknesses and problems in interpreting the diagrams. The problems included superficial processing of diagrams, lack of awareness and skills of interpreting diagram conventions, misinterpretation of temporal relationship among different diagrams or different diagram components. As a result, a number of misconceptions on cell divisions were detected among the students. These included misconceptions related to: (1) changes in chromosome number in cell divisions, (2) crossing over occurring at metaphase I of meiosis, and chromosome arrangement at metaphase I. The study also found that students generally perceived diagrams useful for learning cell divisions, but not for learning biology in general. They seemed to have underestimated the functions of textbook diagrams in representing biology concepts and undervalued the roles that diagrams may play in assessment of their understanding of biological concepts.

The research findings contribute to the literature on misconceptions of cell divisions by uncovering students’ misinterpretation of specific kinds of diagrams as the origin of their learning difficulties. The findings also contribute to the growing literature on students’ visual perception and the power of diagrams for learning from science textbooks. Recommendations were made for textbook authors to improve design of diagrams illustrating scientific concepts, for teachers to equip students with visual literacy skills to learn from diagrams, and for teacher trainers to provide relevant training to pre-service and in-service teachers. Some suggestions for further research were also discussed.