Sanakirja.org

Esimerkit

• In the Filicales the leptosporangium has a specialized spore dispersal mechanism involving an annulus of cells with thick walls that ejects spores explosively as it dries out.
• The characteristic that unites the Filicales as a monophyletic clade is the presence of leptosporangia with an annulus-an area of specialized cells involved in dehiscence.[...]Leptosporangia typically produce only a few spores, and are most commonly homosporous.
• Leptosporangia are unique among vascular plants in (1) developing from a single cell, and (2) having a single layer of cells making up the sporangium wall.