The composition of the earth from it's core to it's crust is organic and is continually evolving albeit over millions of years. In this context could the earth be described as a living organism?

Many scientists will say that the Earth is a living organism. If you want to read several opinions, here is the Google page which lists the links.

earth+living organism - Google Search (http://www.google.com/search?q=earth%2Bliving+organism&sourceid=ie7&rls=com.microsoft:en-US&ie=utf8&oe=utf8)