I was just a little curious about why we sleep? I know it is somewhat about re-balancing hormones, but that can't be all. What causes us to feel tired, and what makes us dreams, and what makes seperates deep sleep from dream sleep (if there IS much of a difference)? Anything and everything?

Thanks Much!

I'd start out with this thread, and work up any further questions you might have, as I'd(or probably anyone else) hate to retype each thing.

 

http://www.scienceforums.net/forums/showthread.php?t=4195&highlight=rem+sleep