Cell polarity as the "logos" of morphogenesis.

1. If a certain character, visible or invisible, does occur in a cell not uniformly but having a tendency to appear toward a definite orientation, we consider that the cell has polarity in appearance of that character with respect to the polarity axis of that orientation.2. The cell polarity is a non-specific property, appearing prior to and maintained throughout actual morphogenesis, so that, it would be an initiator and a leading principle of development. In such a sense, it can be called the “logos” of morphogenesis.3. The cell polarity is considered to be based on an oriented framework system of microtubules supported by microfilaments in the cortical layer of the cell.