(VIDEO-AT-LINK)During a passionate address at historically black Tuskegee University Saturday, Michelle Obama said she refused to let the "sting" of racial bias define her. "Over the years, folks have used plenty of interesting words to describe me. One said I exhibited a little bit of 'uppityism,'" the first lady said. "Cable news charmingly referred to me as 'Obama's baby mamma.' "All of the chatter, the name-calling, the doubting, all of it was just noise," she said. "It did not define me, it didn't change who I was, and most importantly, it couldn't hold me back." Conjuring up the incidents in...