Chapter 31 fungi 09 15 2015 Along with bacteria fungi can break the bonds in cellulose Very important when talking about chemical cycling Fossils have been found that are 460 mya Evolved like plants General characteristics Eukaryotic cells Differ by nutritional mode structural organization and growth reproduction Heterotrophs Can not photosynthesize More closely related to animals not plants About 50 different species that can cause diseases in humans Important medically Athletes foot ring worm Absorptive heterotrophs exoenzymes digest outside of their bodies once broken down absorbed back into cells Two ways to classify fungi Saprobes o Living on dead organisms Parasites o Lives on living things Fungi are important in symbiotic relationship with other organisms Leaf cutter ants grow a fungus for food Tiny ant that rides of leaf cleaning it on the road back to the nest Termites do this as well Yeast only single cellular fungi Kingdom of fungi considered multicellular Base unit hyphae Mat of hyphae mycelium Have no differentiated cell types Have rhizoid not true root Largest organism in the world is a fungus Found in Oregon Some of the parasitic fungi have haustoria Put them into plant cell and it dissolves the cells Absorbs everything out of cells Can actually trap animals nematoad Most specialized parts of fungus deal with the reproductive structure Some of the hyphae have septum Coenocytic hypha not separated Fungi are haploid Dikaryons two haploid cells in one Reproduction can be sexual or asexual Most do sexual but most can do both Make spores by mitosis because haploid Asexual spore mycelium gametophyte FIGURE 31 5 general life cycle Karyogamy fusion of the nuclei Diploid zygote undergoes meiosis to produce haploid spores Spores fall down and germinate then grow into new mycelium Chytrids 1 000 species Mostly aquatic Have flagellum Only fungus with flagellum Chitin in cell wall polysaccharide that contains nitrogen Absorptive Most primitive Zygomycetes 1 000 species Rhizopus Black bread mold Mitosis in sporangium Zygosporangium carries out Karyogamy Two mating types in sexual reproduction Cool sporangia can throw their spores 2m away grow in cow manure Ascomycetes Sac cup fungi Most diverse and largest group of fungi Mildew morel truffle androstenol given off when truffles ready to be harvested from under ground Conidia dust Conidiafor produces the spores Dikaryotic hyphae End up with 8 ascospores 3 stages o haploid n o dikaryotic n n o diploid 2n lichen usually Ascomycota with a cyanobacteria or green algae algae photosynthesizes and gives sugar to the fungus and the fungus in turn provides for algae slow growers very good indicators of pollution in the environment die when exposed to excess pollution parasitism symbiotic relationship not sure between the two a lot of them that are not very good because they are pathogens on plants lose a lot of food each year to fungal diseases smut on corn tar spot fungus on maple leaves ergot grows on rye LSD Glomermycetes Basidiomycetes 30 000 species traditional mushrooms shelf bracket fungi puffballs maiden veil fungus look like a phallus without veil mycelium main organ under the ground when harvesting mushrooms just taking the reproductive structure fungus can break down cellulose can do asexual reproduction but most of the time they don t basidiocarp gills lined with basidia LEARN LIFE CYCLE NEGRA Fairy ring the oldest part is in the middle of the ring o Mycelium can send out exoenzymes to breakdown things in soil No antidote to mushroom toxins Can shut down transcription and translation in liver Penicillium o Fungus that kills bacteria Deuteromycota Imperfect fungi Found in their non reproductive non sexual stage Vast majority go into Ascomycota Yeast unicellular and can be found in many groups Ethylene encourages fungal spores to germinate Histoplasmosis breathing in fungi and getting into lungs Athletes foot Yeast infections 09 15 2015 09 15 2015