Will my Sims 3 I used on my pc work on my mac?

I got The Sims 3 when it first came out in 2008 and I put it on my HP. I am not home right now to get the disc, but I just got a hankerin' to play it again and I now own a mac. I was wondering, can I use that disc to load it onto my mac and then buy mac expansions from there, or will I have to buy a whole new regular Sims 3?