When speaking of bass backbones & Love in the same thread, I'm surprised that "7 and 7 Is" wasn't mentioned. That was one of the songs that really impressed upon me what a bass can do to a song. "Rain" by the Beatles, along with the other side of the 45: "Paperback Writer" were also totally bass driven (BTW wasn't that like the 1st 45 that was released with two "A" sides?), oh, and "Lady Madonna", etc. etc. Don't forget Jefferson Airplane's "White Rabbit" & "Tighten Up" by Archie Bell & the Drells. I always feel compelled to point out how much the bass serves as the backbone in Jimi Hendrix's stuff--e.g. "Manic Depression" & "Fire". Sometimes I think that the basslines that Jimi composed (& often played on the recordings) were nearly as much a legacy as his guitar work.
I realize I'm commenting on an old post. However, I just saw this. Although I agree with everything that is being said here, I'd like to point out that the bass in "Fire" is Noel Redding's bass line that he composed himself. I think on "Manic Depression" he is mostly doubling Hendrix's guitar riff with a few minor variations.