3 9 15 What is the biggest organism ever o Apatosaurus Blue whale Coastal redwood NONE OF THESE o It s a fungus A single clone of the honey mushroom Armillaria can cover more than 2 200 acres 1600 football fields Acres of sick trees has other fungi that are connected to the honey mushroom Main body is in the ground great decomposers primary producers of the bottom of the food web they can drastically increase how fast did organisms are decomposed and turned into nutrients The Diversity of Fungi o What are the key features of fungi Reproductive structure or fruiting body the above ground portion Mycelium the body of the fungus responsible for decomposing the stuff around it by actively releasing enzymes and spreading out the fungus root looking parts Underneath umbrella part there are gills that produce haploid spores Mycelium the feeding network of a fungus The largest non reproductive portion of a fungus Vegetative potion of the fungus Usually underground or inside a decaying or living organism Composed of a woven mesh of hyphae o Hyphae singular hypha are the threadlike filaments of a fungus Some fungi have specialized hyphae to trap prey ex Nematode o Tubular cell wall containing chitin Chitin is produced by a polysaccharide sugar after sugar after sugar etc o Surrounds the plasma membrane and cytoplasm Cell walls of fungi are compose of chitin a structural polysaccharide of modified sugars Polymer w glucose subunits and N containing functional groups Chitin also makes up insect exoskeleton ex Soft shell crabs shrimp crawfish fungus cells walls Septa structures which partially separate the cytoplasm inside the hyphae found in many fungi o Fungi Propagate by Spores Haploid 1n cells which can grow directly into a hypha One copy of each chromosome Ex Puff ball o Sexual Reproduction in Fungi Have to be the same species conditions environmental situations change have to be right and in most fungi there is a system in place that prevent them from reproducing with certain fungi mating types and this helps increase genetic variability because of this To produce more genetic variation than asexual reproduction Hyphae n mating system fusion of compatible hyphae plasmogamy n n heterokaryotic cell a single cell with two nuclei and the nuclei are haploid and different fusion of nuclei karyogamy diploid zygotes 2n meiosis of zygote like structures half needs to be mating type and the other mating type dispersal of spores a new extending strand of hyphae Spores haploid 3 11 15 Asexual reproduction in fungi is good because of genetic variation Both asexual and sexual reproduction produce spores o Sexual reproduction mycelium plasmogamy fusion of cytoplasm heterokaryotic stage karyogamy fusion of nuclei zygote meiosis spore producing structures germination Mitosis still goes on the cells growing to form the mushroom for example o Asexual reproduction mycelium spore producing structures germination Fungal phylogeny o Chytridiomycota 1000 species o Zygomycota 1000 species o Glomeromycota 160 species o Basidiomycota 65000 species for basidia outside 4 haploid basidia o Ascomycota 30000 species form ascus a sac that has 8 asco o generally thought that fungi came to land first had the ability to give off enzymes into the environment actually able to have access to nutrients that animals and plants could not get access to o Fungi to land allowing nutrients to be available so plants can come to land and then after plants then animals like Tiktalik moved to land What are the major groups of Fungi Kingdom Fungi Diversity o Over 100 000 fungal species identified and more are added each year o Five divisions of the Kingdom Fungi o These divisions are based on DNA sequence data on the presence of septa in the fungi and on the sexual life cycle the structures that are formed problematic because some fungi don t reproduce through sexual reproduction 3 18 15 Fungal Divisions o Club Fungi Division Basidiomycota Usually reproduce sexually septa present Produce sexual reproductive bodies basidia o Where the events of karyogomy takes place A lot of diversity in the mushrooms figure of basidiomycota lifestyle Opposite mating types creating the one heterokaryotic type Basidiocarp sexual reproductive body that forms Basidia Basidium Basidiospores after meiosis Fairy ring heterokaryotic basidia Some form the gills of the mushroom What is the ploidy type of eating the mushroom diploid haploid or heterokaryotic All of the above Basidia are generally found on the surface of gills A mushroom fairy ring The mycelium of the basidiomycetes grow very large and can produce a fairy ring at the circumference Plasmogamy happened a lot time ago How do Fungi Interact with Other Species o Need to understand fungal lifestyles Use absorption to obtain their food Three variations depending on the food type o Fungal lifestyles Saprobes decomposers of dead material most fungi Parasites fungi which grow on living organisms Dutch elm disease corn smut athletes foot jock itch yeast infections More worried about parasitic fungi that infect our food sources o Ex rust fungus in wheat Mutualists fungi that live interdependently with photosynthetic organisms Obligate symbiotic relationship need to be together Lichens o Symbiotic relationship between a fungal species and either a cyanobacteria or unicellular photosynthetic eukaryote Mycorrhizae o Symbiotic relationships between fungi and the roots of a plant o Endomycorrhizal growing into the root of the plant o Over 90 of plants have mycorrhizae Plant Reproduction and Development o Diploid trillions of cells etc similar to human development o 1n haploid cells would be found within the flower aspb American Society of Plant Biology o Publications teaching tools Why study plants PLANTS 3 20 15 PLANT REPRODUCTION ASEXUAL Fragmentation SEXUAL Combines genes from 2 different parents offspring genetically different Producing genetic variation between generations Mutations are the ultimate source of variation Sporophyte 2n flowering structure realize from hormone signals to know to become flowering o Multicellular diploid cell Meiosis to produce haploid cells Male Gametophyte o Need to recognize which parts go through this and which structure has meiosis o Pollen grain n o Sperm cells n o megaspore n in the ovary preexisting cells create a diploid cell n o diploid cell goes through meiosis in the ovary and produces one haploid megaspore to divide and produce 4 then divide and produce 8 in ovary
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