tribute greatly to understanding the origins of The plan for this book goes back almost 20 years. Already, at that time, it was possible to recognize organisms. an extraordinary variation in metabolites and To provide the biochemist with a ready over- processes superimposed upon the basic biochem- view of the structural diversity of animals, the book includes a simplified version of animal sys- ical system of animals. Each species, each indi- tematics; for further information on the classifica- vidual, in fact each type of cell of the multicellu- lar organism possesses its own biochemical...