The Hormones: Physiology, Chemistry and Applications, Volume V covers the advances in understanding the nature and function of hormones. This seven-chapter volume is a continuation of Volume IV on the endocrinology of plant and non-mammalian animal hormones. The introductory chapters examine the structure, metabolite actions, and some other chemical aspects of pituitary hormones. The following chapter explores the physiological, biochemical, and phylogenetic aspects of thyroid hormones, as well as brief description of thyroid cytology and process kinetics related to the thyroid. This chapter also presents mathematical models describing the processes of accumulation and binding of iodide in the thyroid, along with the release and metabolism of thyroid hormone. These topics are followed by discussions on the methods and concepts used for in vivo studies with labeled steroids in man. A chapter focuses on the role of hormones on tumorigenesis and tumor growth. Another chapter considers the concepts of mode of action of other hormones, such as insulin, epinephrine, and estradiol. The concluding chapter treats some examples of endocrine disease from the standpoint of the biological problems. Endocrinologists, physiologists, biochemists, phylogeneticists, and researchers who are interested in expanding knowledge on hormones will find this book invaluable.