Tropes and Memes

Can someone help me out with the difference between tropes and memes, perhaps with examples of each? I’ve been having these interesting conversations with my older son about Internet-based, popular culture memes. A lot of what he describes as memes, I would have called tropes. But I don’t really know what I’m talking about and the usual dictionary definitions are not helping me much. In practice, what do “we” mean, inside the academy and out, by these terms?