The enzymatic weakening of the contacts between the cells of the transfusion tissue permits penetration. Both pollen and stigma or style, respectively, supply the enzymes. The tuning of these activities, so that the pollen tube finds its way guided by the anatomy of the style works trouble-free only with pollen of the same species. The Fusion of Two Cells. A plant cell can neither be penetrated by another cell nor fuse with it as long as it is surrounded by a wall.
Fusion occurs only, if the wall is missing or if it is locally perforated.
At this stage becomes the sequentially orchestrated effect of several enzymes necessary for the union of the two cells. The cytosceletons restructures so that intracellular components are distributed anew.