Anyway I think the point is clear. Physicists try and explain the atom and it's make up to understand every thing else. They kind of work at the root. Chemists work at a higher level from the molecule. That leaves biologists to look at the basic building blocks as the complex set of chemicals that are dna and the result of this code which is a cell.
My understanding is that the large life forms evolved as bacteria started to live symbiotically almost as their own little community. Overtime they worked so well together that the could specialise on particular jobs because each bacteria was able to provide something the others needed such as ; movement, structure or vitamins and minerals. Over millions of years this eventually evolved in to bones, muscles and internal organs but we can still be thought of as giant clumps of bacteria all working together on a massive scale.
So that's a brief history of what I understand. Hopefully it's now clear why an understanding of the smallest living part of us, through understanding one of its relatives, can unlock the secrets of the whole and help us understand what we need to survive and flourish.
To this end I came across an article explaining a break-through in the understanding of how energy is actually transferred in and out of the body. Not only can we learn a little about what makes us perform well because we learn that riboflavin (vitamin B-12) is the main compound involved, this in turn highlights the importance seemingly miniscule compounds have in our daily lives. What also shows is how advanced even these tiny micro-organisms are and how much we can learn but studying them even a little. It sounds as those the electrical industry is going to learn a lot from them and it should make our lives a lot better and hopefully even reduce the pollution we create in our search for energy.
edit 20090820 14:38
Carrying on the them on a slight tangent. Just came across an artile on microbial fuel cells. I've been wondering if this was an option for the future. Thought I'd note it to show that we're still learning so much from nature on a daily basis.