Australia-wide consensus was reached on seven core concepts of physiology. The “movement of substances” core concept with the descriptor “the movement of substances (ions or molecules) is a fundamental process that occurs at all levels of organization in the organism” was unpacked by a team of three Australian physiology educators from the Delphi Task Force into hierarchical levels. There were 10 themes and 23 subthemes arranged in a hierarchy, some 3 levels deep. Using a 5-point Likert scale, the unpacked core concept was then rated for level of importance for students to understand (ranging from 1 = Essential to 5 = Not Important) and level of difficulty for students (ranging from 1 = Very Difficult to 5 = Not Difficult) by the 23 physiology educators from different Australian universities, all with a broad range of teaching and curriculum experience. Survey data were analyzed using a one-way ANOVA to compare between and within concept themes. The main themes all were rated on average as important. There was a wide range of difficulty ratings and more variation for this concept compared with the other core concepts. This may in part be due to the physical forces such as gravity, electrochemistry, resistance, and thermodynamics that underpin this concept, which in themselves are inherently complex. Separation of concepts into subthemes can help prioritize learning activities and time spent on difficult concepts. Embedding of core concepts across curricula will allow commonality and consistency between programs of study and inform learning outcomes, assessment, and teaching and learning activities.