Is This Enough to Trigger Growth?

I'm 17 and I lift 5 days a week and work a different body part each day. (Mon-chest, Tue- back, Wed- bis/tris, Thurs- shoulders, Fri- legs) For the most part I get in 12 sets total for each body part. So my question is.....is 12 sets enough for significant muscle growth? I keep it to 12 because i don't want to overtrain my muscles. Should I be doing more since I only work a certain body part once a week?