This book aims to present the important features of mammalian physiology in a concise manner. General principles and underlying mechanisms are emphasized and relatively non-vital details are minimized. Attention is directed to cell physiology, which serves as a basis for body functions. The book shows that the processes that take place in individual cells are usually applicable to each organ system as a whole. The major emphasis of the book is on regulation. The mechanisms that regulate the functions of the individual organ systems are described and are then applied in the complex interactions between the systems as they maintain the constant internal environment that is important for the optimal function of the constituent cells. All systems are then tied together in the final chapter describing exercise physiology in order to explain how the body successfully integrates its varied functions to perform a specific task.