An important part of the biology subject matter in school is the biological processes in the human body and health. In the Swedish curriculum these are present in all years of the compulsory school. Anyhow, students do not have an overall understanding of health and bodily functions. The misunderstandings of the nutritional processes of the human body have been reported by several authors. We have been teaching physiology to preservice teacher and biology students for several years trying to reach a better understanding of processes in the human body. The present study shows teaching of health and body starting with a discussion about ticks and the various diseases they spread in the Stockholm area. Nine preservice teacher students participated in four weeks of biology studies, including ecological processes and organisms’ life cycles. The last week was devoted to body and health. The idea was to begin with the circulatory system as students often focus on the various functions of the organ but forget to link it to the blood system. By connecting to the students' previous knowledge of organisms and ecosystems to body and health, we started with an introduction of tics by going out collecting and investigating their morphology and life cycle and continued with a video clip showing how the virus and bacteria are spread through the blood. The following lessons contained function of body systems, nutrition and the immune system. After this the students wrote reflections from three different lessons about their learning and what was surprising. They also wrote a lesson plan for teaching body and health in primary school (year 4-6). At the end of the course, the students had an examination in three parts where one was concentrated on body and health. Results from the reflections and the written exam showed that the students understood the interaction between the different parts of the body better and the importance of the circulatory system, but also between different organisms and how they may affect each other. The inclusion of ticks in the course increased the understanding.