This book provides senior undergraduate and graduate students taking courses in biochemistry with an up-to-date description of the regulation of mammalian metabolism. Emphasis is placed on the mechanisms involved, an aspect which is poorly covered by existing texts. The book is divided into three sections, the first two of which describe in detail the mechanisms by which the metabolism of a cell is regulated by both internal and external factors. In the last section these molecular mechanisms are related to physiological regulation of individual tissues and the integration of the response of individual tissues to changes in the state of the whole organism