Dehiscence (botany) through a split on the outer side (relative to the center of the flower), this is extrorse dehiscence, and if the pollen is released from the inner side, this is introrse dehiscence. If the pollen is released through a split that is positioned to the side, towards other anthers, rather than towards the inside or outside of the flower, this is latrorse dehiscence. The stomium is the region of the anther where dehiscence occurs. The degeneration of the stomium and septum cells is part of a developmentally timed cell-death program. Expansion of the endothecial layer and subsequent drying are also
Annulus (botany) dissolve to allow the cap to fall off and the spores to be released. Annulus (botany) An annulus in botany is an arc or a ring of specialized cells on the sporangium. These cells are arranged in a single row, and are associated with the release or dispersal of spores. In leptosporangiate ferns, the annulus located on the outer rim of the sporangium and serves in spore dispersal. It consists typically of a ring or belt of dead water-filled cells with differentially thickened cell walls that stretches about two-thirds around each sporangium in leptosporangiate ferns. The thinner walls on the