As has been mentioned, the interview is composed of behavioral questions. All of the questions are of the "Describe a time when you showed [characteristic]." You can look at the interview feedback here:
http://studentdoctor.net/schools/school/ttu-pharm/survey/26
I won't say which questions are or aren't asked, and the questions change slightly from year to year anyways, but it will give you a good idea of what will be asked. Any questions that dont follow the "Describe a time you ____" format aren't part of the questions we are required to ask, but may be something that your interviewers want to know about you. It's a good idea to have a few examples prepared ahead of time that can fit into different categories. For behavioral questions you want to set up your answers in this way: 1) Describe the situation 2) What did you do 3) What was the result. Try to be as descriptive as possible in your role in the situation. Your interviewers will also give you a little bit of time to think of an answer if you can't immediately answer a question.
To prepare, I think the best thing to do is to practice. You don't want to memorize any answers, it comes off as robotic, but still you want to practice being comfortable and confident in the way you answer questions. Your nonverbal cues play just as important a role as your answers do. While this isn't something that we score in an interview, confidence is something that has influenced me to give a higher score for an answer. If it helps, try to make your practice sessions as real as possible. That way, when you do the real thing, it wont be as foreign or nerve-racking a situation.
Lastly, have a few questions for your interviewers. This might be something that I like, but I think it shows that you're interested in the program and are comfortable in what is likely a high stress situation for you. I hope this helps. Feel free to ask me any more questions or PM me if you'd like. Good luck!