Some science behind the scenes
Body as hardware
Most people shy away from the idea that the body is more like a machine than a work of art. But it is realistically speaking both.
We watch films like the Terminator and are happy to accept the idea that robots – machines with human characteristics – may exist one day – both good and bad. We are perhaps less happy to think of ourselves as a form of biological robot. Furthermore, the idea that the body can be looked on as similar to computer hardware seems to many who view the body as a wondrous thing to be even slightly sacrilegious.
But the idea is not so preposterous. Computer scientists have long modelled [albeit often subconsciously] computer technology on human and animal attributes. A computer has a central processor [brain] and peripherals [memory, hands, feet, eyes, ears, nose, mouth etc etc]. We may also have communications equipment …
Furthermore, researchers are now building computers from biological components. This branch of computing is known as DNA computing, and is a form of computing which uses DNA, biochemistry and molecular biology, instead of the traditional silicon-based computer technologies.
This field was initially developed by Leonard Adleman of the University of Southern California, in 1994, but in 2002, researchers from the Weizmann Institute of Science in Rehovot, Israel, unveiled a programmable molecular computing machine composed of enzymes and DNA molecules instead of silicon microchips. The advance was published in the journal Nature in 2004. This first biological computer has been built with the specific purpose of diagnosing cancerous activity within a cell, and then releasing an anti-cancer drug upon diagnosis.
It is possible to make DNA computers using DNA nanotechnology - a subfield of nanotechnology which uses the unique molecular recognition properties of DNA to create new structures out of DNA. DNA is used as the structural material and the DNA computer is made using the nanotechnology. This has possible applications in molecular self-assembly.
We are going further and further down into smaller and smaller units of processing and eventually of course we may reach the atom.
Leonard M. Adleman (1994-11-11. "Molecular Computation Of Solutions To Combinatorial Problems". Science (journal) 266 (11): 1021–1024.
Yaakov Benenson1, Binyamin Gil, Uri Ben-Dor, Rivka Adar, Ehud Shapiro (2004-04-28) "An autonomous molecular computer for logical control of gene expression". Nature (journal)429: 423–429.
Martyn Amos (June 2005). Theoretical and Experimental DNA Computation Springer. ISBN 3-540-65773-8. — The first general text to cover the whole field.
Gheorge Paun, Grzegorz Rozenberg, Arto Salomaa(October 1998). DNA Computing - New Computing Paradigms. Springer-Verlag. ISBN 3-540-64196-3 — The book starts with an introduction to DNA-related matters, the basics of biochemistry and language and computation theory, and progresses to the advanced mathematical theory of DNA computing.