L8 The Ascomycota (Part 1) Flashcards
What are the seven phyla of fungi?
Microsporidia, Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, Glomeromycota, Ascomycota, Basidiomycota.
What is unique about the dikaryon phase in fungi?
It involves two paired nuclei that do not fuse, allowing genetic diversity.
How many species are estimated in the phylum Ascomycota?
93,000 species.
What are key characteristics of Ascomycota?
No motile cells, cell walls with chitin, septa in hyphae, and ability to grow in drier conditions. can exploit a wider range than zygomycetes
What is anastomosis in Ascomycota?
The fusion of compatible hyphae to exchange nuclei.
What is the teleomorph phase in Ascomycota?
The sexual reproduction stage where ascospores are formed.
Describe the process of ascus formation.
Karyogamy and meiosis occur, resulting in eight ascospores formed from a dikaryotic hypha.
How are ascospores released from the ascus?
They are released through various mechanisms, including active and passive methods.
What are the four types of ascoma?
Apothecial, perithecial, pseudothecial, and cleistothecial.
Describe an apothecial ascoma.
It has an exposed fertile layer and releases many ascospores at once, often wind-dispersed.
What is a perithecial ascoma?
It has a small opening and releases ascospores one at a time, often caught in sticky droplets.
What distinguishes pseudothecial ascoma?
It has an enclosed hymenium and contains bitunicate asci.
How does a cleistothecial ascoma function?
It has no opening; spores are released when the ascoma breaks down.
What is the significance of asci in Ascomycota?
Asci are the structures where meiosis and spore formation occur.
Name two important examples of Ascomycota.
Saccharomyces cerevisiae (yeast) and Penicillium chrysogenum (source of penicillin).
