Practice question

Basidium constitutes characteristic meiosporangium of Basidiomycota, club-shaped dikaryotic cell within hymenium of gills, pores or other sporulating surfaces of mushrooms. After karyogamy, meiosis produces four haploid nuclei migrating onto sterigmata forming basidiospores externally above basidial surface. Ascus sac-like housing ascospores inside, sporangiophore supports sporangium in zygomycetes, conidiophore bears conidia asexual. Club shape maximizes spore exposure for forcible discharge using surface tension catapult mechanism called Buller's drop. Basidium morphology varies: holobasidia non-septate, phragmobasidia septate in rusts, but clavate shape conserved. Mitosome identification utilized immunofluorescence targeting iron sulfur cluster assembly proteins confirming mitochondrial evolutionary origin despite minimal proteome.