What do we mean when we talk about "structure/function" relationships?

In multiple studies "structure/function" has been identified as an important core concept in biology and physiology. Teachers expect their students to be able to use this concept in making sense of physiology. However, it is unclear exactly what physiologists are referring to when they use the term "structure/function." Here I first offer examples of four different ways in which I have used the term in the classroom. Then, I propose a conceptual framework that is an explicit statement of the "structure/function" core concept that can be used by teachers and their students as they attempt to master physiology. Determining whether this conceptual framework is completely accurate and whether it will prove useful in the classroom will require feedback from physiology teachers who attempt to use it in their classroom with their students.