[Architecture of physiological functions: the same basis but new aspects].

The principles of physiological functions formulated by J. Barckroft (constancy of the internal medium, reserves, any adaptation as an integration, principle of antagonism, doubling of mechanisms) are compared with principles of modern physiology. The place and role of physiology in the life sciences are discussed. The necessity of taking into consideration 4 level of regulation of functions (the nervous system, hormones, autacoids, physicochemical factors of the extracellular fluid) is substantiated, as well as the necessity of identification of 4 levels of organization of physiological systems. The main role of the water-salt homeostasis in maintaining the cell volume is suggested. Significance of various types of receptors and second messengers in regulation and modulation of functions is shown.