This text aims to bring to the attention of undergraduate students of biochemistry the many exciting developments in cell and molecular biology in recent years and their important implications for the practice of medicine. Emphasis is placed on such topics as membrane structure and function and hormone action and secretion, where current knowledge of macromolecular and cellular structure and function will contribute most to understanding the underlying pathology of common multifactorial diseases. The book also outlines the basic features of recombinant DNA techniques and their probable impact on the diagnosis, treatment and knowledge of disease processes. This text will interest undergraduates in pre-clinical medicine, biology and biochemistry.