Presentation on theme: "The Study of Fungi is called Mycology"— Presentation transcript:
1 The Study of Fungi is called Mycology Kingdom FungiThe Study of Fungi is called MycologyWhat is probably the largest living organism on earth has been discovered in the Malheur National Forest in eastern Oregon. A fungus living three feet underground is estimated to cover 2,200 acres. After testing samples from various locations, scientists say it is all one organism. Officially known as Armillaria ostoyae, or the honey mushroom, the fungus is 3.5 miles across and takes up 1,665 football fields. The small mushrooms visible above ground are only the tip of the iceberg.Experts estimate that the giant mushroom is at least 2,400 years old, but could be 7,200 years old.
2 Characteristics of Kingdom Fungi In order to belong to the Kingdom Fungi, organisms must:Be MulticellularHave Eukaryotic cellsBe HeterotrophsMust have cell wallsMost fungi are sedentary..(they don’t move around, they live their lives anchored somewhere)
3 Cell WallsThe cell walls of Fungi are made of Chitin (Chitin is a sugar… the same substance which makes up the exoskeleton of insects)Some fungi have cross walls, or septa, which divide the filaments into compartments having a single nucleus.septum
4 Some cells lack septa and are multi-nucleated, or coenocytic (have many nuclei)
5 Digestion takes place outside the body (extra-cellular) Fungi are Absorptive Feeders …they simply ingest (absorb) digested foods thru their cell walls
6 only seen when the fruiting bodies emerge…. By then it’s too late FactsFungi live and grow in their foodonly seen when the fruiting bodies emerge…. By then it’s too late
7 FactsCell Walls are either partial or absent………. The cytosol is circulated through simple cyclosis.
8 Ecological RoleThe major role of Fungi is as Decomposers (they are the great recyclers)…. They are Saprophytes
17 Fungi spend most of their time as haploid (n) organisms Fungi spend most of their time as haploid (n) organisms. However, most form a temporary diploid structure for reproduction. The three following stages occur during sexual reproduction…. plasmogamy, karyogamy and meiosis.
18 Plasmogamy is the fusion of two haploid cells from two separate fungi strains. The fusion forms a dikaryon (a cell with the two haploid nuclei). A hypha containing a dikaryon is called a dikaryotic hypha.
19 Karyogamy is the fusing of the two haploid nuclei of a dikaryon to form a single diploid nucleus.
20 Meiosis of the diploid nucleus restores the haploid number.
21 Fungi Reproduction Fungi reproduce both sexually and asexually. Asexual reproduction includes:1. fragmentation: the breaking up of hypha2. budding: the pinching off of a small hypha outgrowth3. asexual spores: there’s two kinds of asexual sporesa. Sporangiospores are produced by sporangia which arelocated on top of a filament called a sporangiophore.b. Conidia are formed at the tips of specialized hyphaecalled conidiophores.
22 Asexual Spores Sporangium: Produces the sporangiospores Sporangiophore:Holds up thesporangium
23 Asexual SporesThe Conidiophores look like tubes… the conidia look like small black dots inside the tubes.
24 Classification of Fungi mostly classified by the shape of the “Fruiting Bodies” The “Fruiting Bodies” are the reproductive structures.Phylum Zygomycota (bread mold)Phylum Basidiomycota (mushrooms, puff balls, bracket fungi)Phylum Ascomycota (cup fungi)Phylum Deuteromycota (Imperfect fungi)
25 Phylum Zygomycota A common Zygomycota is Bread Mold Hyphae lack septaSexual reproduction is by conjugation (fusing) hyphae from two different strains, followed by plasmogamy, karyogamy and meiosis and the production of Zygospores.
26 Zygomycota Sporangium: Produces the spores Sporangiophore: Holds up thesporangium
30 Have Septa and reproduce sexually Phylum BasidiomycotaMushroomsPuffballsShelf (Bracket) FungiHave Septa and reproduce sexuallyUnderground hyphae intertwine and grow upward to produce a reproductive structure called a basidiocarp. This basidiocarp is what we call a mushroom.Basidiospores are produced on the basidia, reproductive structures, which are found on the edges of the gills.
38 The largest group of fungi Phylum AscomycotaCup FungiYeastMildewsThe largest group of fungiNamed for the reproductive sacs or Asci that form near the tips of the hyphae. Ascospores are formed here and released into the air when the ascus ruptures. These spores germinate to form new hyphae.
51 Lichens • symbiotic association held in a hyphae mesh alga provides food, fungus provides physical environment•air pollution detection
52 Many Fungi are involved in Mycorhizzae relationships…Over 90% of plants have fungi associated with their roots. The fungus absorbs and concentrates phosphates for delivery to the plant roots. In return, the fungus receive sugars synthesized by the plant.