Here's how I see it:
"Why you would be a good physician?"
= what are the general qualities about your personality (punctuality, dedication, compassion, etc) that we'd look for a good physician
"Why are you picking TUCOM?"
= what about this curriculum, this campus, this faculty, etc interests you
for instance, perhaps you are Jewish and you like that they conform to Jewish practices moreso than a non-Jewish school like DMU (you don't have to say DMU of course)
"Why should the admissions committee take you?"
= if you lined yourself up with nine other premeds, what are the things that would distinguish you... diversity... for instance, you were an EMT, five other people weren't, you are a violinist, the other nine aren't, etc etc
This requires that you know what the general resume of a premed application looks like (and you do... Mdapps)
Anyway, good luck!