THE GREY ZONE. “A single-celled bacterium is alive, but if you separate the macromolecules that combined to create the bacterium, these units are not alive. Based on our knowledge of macromolecules, we would not have been able to predict that they could combine to form a living organism, nor could we have predicted all of the characteristics of the resulting bacterium.”
http://www.nature.com/scitable/topicpage/biological-complexity-and-integrative-levels-of-organization-468