The second type of differentiation is that between supporting axis and assimilating appendages.
The process is essentially a polar linear action, or differentiation from a common centre.
1.Examples of the differentiation of the cells of plants.
Among the Green Algae the differentiation of cells is comparatively slight.
In the more highly developed series, the mosses, this last division of labor takes the form of the differentiation of special assimilative organs, the leaves, commonly with a midrib containing elongated cells for the ready removal of the products of assimilation; and in the typical forms with a localized absorptive region, a well-developed hydrom in the axis of the plant, as well as similar hydrom strands in the leaf-midribs, are constantly met with.