[Levels of organization of living systems: cooperons]

All creatures living on Earth are traditionally being considered in the context of structural-morphological approach, in frame of which there are considered various living systems (for instance, organisms and ecosystems) that have different sizes and organization and use different resources for their existence. These characteristics are sometimes added by some particular functional and ecological characteristics, but usually with respect to the structural ones. We believe that such traditional approach, although illustrating, but distracts from the circumstance that any living system is to be considered an integrated structural-functional complex, the maintenance of existence of this system being impossible without the processes occurring constantly in it and aimed at preserving this complex. This leads us to the concept of cooperons--the self-preserved dynamic structures existing only as a result of various specifically organized cooperative processes (their intensities can vary depending on circumstances). From our point of view, all living systems are cooperons of different hierarchy levels. Some other systems, specifically the symbiotic ones, also are cooperons. In frame of this concept, it is possible to discuss functioning of living systems of different types of organization in a new context closer to physiologists, both for the case of "norm" and for the situation when the cooperative interrelations of parts of the system are impaired (for instance, in systemic diseases).