Clamp connections are observed in Basidiomycetes [club fungi). During nuclear divisions of the dikaryoric cell, special structures called the clamp connections are formed. These clamp connections ensure that the sister nuclei of the dikaryon, at each division, separate into daughter cells.
Torula stage of fungus is observed in Zygomycetes. In Zygomycetes the zygospore germinates to produce a hypha, the promycelium with terminal sporangium.
In Oomycetes one of the flagellum is of tinsel type and the other of whiplash type. The hyphal wall chiefly consists of β glucans and cellulose and not chitin. The mycelium is extensive an coenocytic.
In Ascomycetes the spore of sexual stage (meiospores) which are known as the ascospores are endogenous in origin. They are produced within sac-like structures called asci which very in shape.