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BIO 123 Notes 1/27/2010 Fungal evolution Ascomycetes Yeasts, cup fungi, morels, truffles, pink brown blue green molds Some accomycetes form mycorrhizae, others form lichens Basidiomycetes Lichen Combination of fungus and photoautotroph Lichens have 3 main growth forms, crustose, foliose, and fruticose Photoautotroph provides the fungus with shelter, water, minerals, and organic compounds. Decomposers Most fungi are decomposers Break down organic compounds into simpler nutrients that can be recycled Mycorrhizae Mutualistic relationship between fungi and roots of plants Fungus supplies water and nutrient minerals to plant Plant provides sugars to the fungus Useful fungi Used as food, mushrooms, morels Production of beer, wine, and bread Production of cheese and soy sauce Used to make citric acid and other industrial chemicals Research Fungi are model organisms for molecular biology and genetics Medications Penicillin and other antibiotics Pathogens Ringworm, athlete?s foot, yeast infection, candidiasis Plant diseases Hyphal branches penetrate plant cells, wheat rust, Dutch elm disease, chestnut blight Protists Plants Monophyletic group including red and green algae and land plants Red algae Mostly multicellular seaweeds, warm tropical ocean waters, incorporate calcium carbonate in cell walls which is important in reef building Green algae Diverse in size, structural complexity Seedless plants Colonization of land plants Waxy cuticle protects against water loss Stomata, for gas exchange needed for photosynthesis Vascular transport system In ferns or other vascular plants Xylem conducts water and dissolved minerals Phloem conducts dissolved sugar Charophytes Bryophytes Nonvascular, lack xylem and phloem Dominant gametophyte generation Mosses 1 Mosses 2 Zygote Mosses 3 Meiosis occurs within the capsule producing spores Liverworts Flattened