In short...the TSA allows you, in a quart sized ziploc baggie, 3 oz containers of liquids, gels. These items, in regular sized containers are allowed in your checked bags. Anything larger than the 3 oz container, in the ziploc baggie will be confiscated. As for whether or not those containers have to be 'original' containers aka travel sizes, we aren't sure. Some have had no issues with the clear, toiletry bag type containers, while others have had a problem at security. Play it safe and either buy the travel sizes or get other travel sizes, empty them, and refill with what you need.
Head to the TSA site..you'll get a ton of info there.