An overview of the functioning systems of the human body. The physiology of cells as well as the muscular, nervous, circulatory, respiratory, endocrine, digestive and urogenital systems is explored. Emphasis is placed on the integration of the individual function of different cells and organ systems into a functional whole, the feedback mechanisms that account for necessary balances and the consequences of disease. Examples of engineering approaches used to monitor physiological processes and correct physiological deficiencies are included.