Subject: What is the difference between a structual and a physiological adaptation?

 The text I have differentiates between physiological and structual
adaptations. It gives teeth as an example of stuctual adaptation but
aren't teeth a part of the digestive system? So aren't they a 
physiological adaptation also? If there is a difference between these
tow types of adaptations(structual and physiological) could you please
explain it.

Re:What is the difference between a structual and a physiological adaptation?