Exactly!! Por + o = pelo, por + a = pela (plural forms: pelos, pelas)
Thanks for the confirmation. Also, thanks for being so active on the discussion boards! I learn quite a bit from your comments! I've been hearing Portuguese for years now in the house because of my wife and boys speaking together. I understand it so so, but I'm having so much fun now because I am starting to participate in discussions thanks to Duolingo and contributors like you!