The concept that plural groupings can enter into the principal part of the nucleus puts the role of the nucleolus in a new light. It was accepted for a long time that the nucleolus represents only the reserve material necessary for metabolism of the nucleus. The strong positive electrical character of the nucleus, as recognized through its rather alkaline reaction, would give it roles more important than that of the other constituents. According to a work hypothesis which we advance, successive nucleolar formations would represent the principal parts of hierarchic organization below the nucleus level. In chromonemata, chromosome and nucleus, the parts corresponding to the nucleolus can be recognized. These formations are grouped together with genes to form the principal part of the chromonemata. Similarly, chromatine formations representing entities of the same level as the respective nucleolar formations, will form together the groups characterizing the principal part of chromosomes. In the nucleus, the nucleolus is joining the other formations to form its principal part.

Protoplasmatic Formations

In the cell, a hierarchically superior entity, a similar condition also appears to persist. The protoplasmatic formations with ribo nucleic acid can be conceived as representing entities of a nuclear level, that is, a level similar to that of the nucleus. Together with the nucleus they would form the group corresponding to the cell. This kind of evolution of entities in relatively separate parallel lines, with their further grouping together to form principal parts for new entities, is part of the typical pattern of organization especially evident in the biological realm.

Boundary Formations

We have mentioned that groupings of several entities would not be sufficient to form a new entity so long as the secondary environmental part is not isolated from the medium from which it originates. Consequently, the new entity appears only when a distinct boundary formation is formed. Progressive hierarchic development is dependent upon the appearance of such boundary formations. For the first biological entities, the radicals, the boundary seems to be more an energetic property than a morphologically organized formation. For the molecules, it can be considered to consist of molecular surface forces, recognized as the van der Waals cohesion forces. A similar but more apparent boundary formation can be found in higher molecular complexes, especially the micelles. The molecular arrangement at the surface of micelles separates them from their environment and conse quently insures their identity. In the case of morphologically identifiable entities, of course, boundary formations can be easily recognized. Chromomeres are well defined and separated from the chromosomal sap. The chromosomes, in turn, show a real membrane just as the nucleus and the cell do. The next higher entity, the tissue, is bounded by the endothelial cellular layer, separating the interstitial formations from the lymphatic spaces. Usually the boundary of organs which have tissues as principal and lymph as secondary parts is represented by organized blood vessels. As far as the organism is concerned, the mucous membranes and skin are boundary formations. (Fig. 5)

Hierarchic Interrelationship

Viewed as a heterotropic effect, hierarchic organization can be considered to be a method of conserving existing entities as such, in spite of changes occurring in the environment. Teleologically speaking, by entering into the formation of a new and superior entity through the system of hierarchic organization, each entity, in fact, protects its own individuality. The hierarchic organization makes it possible for each entity to continue to live in a medium which corresponds to its own environment. The constituents of the secondary part in the new entity are chosen to correspond to the environment in which the principal part of the entity has existed. The successive secondary parts, added during the hierarchic development, act as multiple protective buffers for the first entities, thus insuring their unaltered conservation in spite of continuous changes in the environment brought about by increasing homotropy.