well for communication (sorry if youre not doing this but this is the clearest example i think), you have to learn about the structure of the ear.
now obviously it is not easy to look inside the human ear, so models are usually used to teach students about the features of the ear and their functions. this helps students to be able to link physiological features to their functions.
however, models themselves dont do very much, and should always be accompanied with information from textbooks etc