Fungal Groups

Ascomycetes Basidiomycetes Imperfect Fungi--Deuteromycetes Zygomycetes

Fungus-related terms

Saprobe Saprophyte Hyphae Mycelium Fruiting body Chitin conidia

Fungi

Cellular Characteristics• Multicellular• Eukaryotic• Heterotrophic• Have cell walls reinforced with chitin• Usually haploid• Diploid only during sexual

reproduction

Basidiomycetes

Examples—mushrooms, rusts, smuts, puffballs Basidia—club shaped reproductive structure

found on the gills. Mating strains Fusion Dikaryotic hyphae Nuclear fusion Zygote—diploid Meiosis Formation of haploid spores Germination

Basidiomycetes

Ascomycetes

Sac Fungi Truffels, Morels, Penicillium, Yeasts,

Candida albicans, Saccharomyces cervisiae, Sordaria

Ascus ascospore

Ascomycetes

Zygomycetes

Terrestrial Fungi Examples—Bread Mold, many

disease-causing parasitic fungi, Rhizopus stolonifer,

Zygosporangium Zygospores

Zygomycetes

Imperfect Fungi

Taxonomic holding station Scientists have not discovered a

sexually reproductive stage in these organisms

Candida and Penicillium were both once categorized in this group.

Fungal Symbiosis

Mycorrhizae—Mutualistic association between tree roots and fungi. Help to increase water absorption.

Lichens—Mutualistic association between fungi and cyanobacteria. Play a role in primary succession.

Fungal Diseases Ascomycetes

• Aspergillus—Aspergilloses—allergies; sinus, ear, and lung infections.

• Candida albicans—yeast infections, thrush• Claviceps purpurea—ergotism• Ophiostoma ulmi—Dutch elm disease• Cryphonectria parasitica—Chestnut blight• Trichophyton tonsurans –ringworm• Trichophyton mentagrophytes and Trichophyton rubrum --Athlete’s

foot

Basidiomycetes• Amanita—Severe poisoning• Ustilago maydis—corn smut• Puccinia graminis—Wheat rust

Mycorrhizae

Meiosis in Sordaria

Ascomycete Fungi Hyphae Mycelium Fruiting Body Asexual Spores--Conidia Sexual Spores--Ascospores Ascus Fungus is usually Haploid.

Meiosis in Sordaria

Fusion of Mycelia forms Diploid cells.

Undergoes meiosis to form ascospores.

Perithecium or Fruiting Body Tan and Black Spore Producers

Life Cycle of Sordaria

Sordaria (Sexual Spore Formation without Crossing Over)

Sordaria (Formation of Sexual Spores with Crossing Over)

Stereomicroscope View of Hyphae and Fruiting Bodies

Sordaria Ascospores with no crossing over

Sordaria Ascospores with crossing over

Sordaria Ascospores with crossing over