Page:Defensive Ferments of the Animal Organism (3rd edition).djvu/145

 like to discuss more closely what is, in our conception, the relation of the micro-organisms to the cell complex of the host.

Let us return for a moment to the conception we developed at the commencement of this work, according to which the organism, under normal conditions, represents a whole closed in itself. We have already pointed out that the harmony of all the processes going on within the whole complex is perturbed, as soon as disharmonious kinds of cells settle inside it; that is, species of cells which have their own metabolism, and their own specific structure. On the one hand these cells have to be fed, and on the other they give off the products of their metabolism, and perhaps also secretions of various kinds, to the exterior. In order to be able to make use of the nutritive material supplied by the host, which is at first disharmonious with their cells, they also must possess ferments which will make the food accessible. It is conceivable that the substances belonging to the host are first absorbed by the cells, and then transformed in their interior, but it is more likely that the invaders give off ferments externally, which decompose the nutritive media around them, and prepare it in that way for absorption. The resulting decomposites are then taken up by the cell. A reconstruction must be made in any case, and especially when the substances are intended, for the building of new cells.