The United Federation of Planets is governed by an elected council, with representatives from every major member planet. Given the tendency of Humans to settle anywhere at least marginally habitable, they do wind up dominating the political scene; however, other species do get a look-in. (In the MMO Star Trek Online, in 2409 the President of the Federation Council is Annek Okeg, the first Saurian ever elected to that office.)
The Ferengi seem to think of the Federation as being in fact run by Humans, in much the same way they themselves dominate the Ferengi Alliance.
Also, people from Earth tend to go on about the Federation being somehow "beyond" money - but the post-scarcity economy of freely-available replicators seems to exist primarily on the core worlds (Earth, Vulcan, Andor, and so on). In the episode "The Trouble With Tribbles", Deep Space Station K-7 had a bar that dealt in "credits" (the barkeep arranged to buy tribbles for six credits each from Cyrano Jones, then tried to sell Lt. Uhura a tribble for ten credits). In some episodes of TNG and DS9, there are references to expenses, something you'd think a true post-scarcity economy wouldn't even notice. (Then again, Capt. Sisko waxed rather eloquent on that topic in one DS9 episode: "On Earth, there is no poverty, no crime, no war. You look out the window of Starfleet Headquarters and you see Paradise. Well, it's easy to be a saint in Paradise, but the Maquis do not live in Paradise. Out there in the demilitarized zone, all the problems haven't been solved yet. Out there, there are no saints — just people. Angry, scared, determined people who are going to do whatever it takes to survive, whether it meets with Federation approval or not!")
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.