The aim of this study is to examine pre-service science teachers’ opinions about holistic approach to science. The participants of this case study consisted of 6 elementary pre-service science teachers. While choosing the participants, the electrical energy inventory was administered to 62 pre-service teachers. The data were collected by using a semi-structured individual interview. The findings of the study showed that pre-service science teachers have lack of knowledge and misconceptions about transmission of a nerve impulse, electrical circuit, and electrochemistry. In the lights of findings pre-service science teachers could not interrelate these concepts as holistically.