Biodiversity kingdom fungi PDF

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this is a study guide for exam 2, on kingdom fungi...

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Meiotic Types: (Lifecycles in Eukaryotes)  Zygotic: Zygote (diploid/2n structure formed by syngamy), engages in meiosis typically producing genetically unique, haploid (n) spores.  Example: zygomycete fungus  Gametic: Diploid (2n) organism produces haploid (n) gametes through meiosis.  Example: animals/ humans  Sporic: Diploid (2n) organism produces haploid (n) spores through meiosis.  Example: plants Ex. Notes: Mitosis (growth)= asexual or sexual, requires whatever ploidy Meiosis=sexual, requires diploid (2n) cell 2 types of cell division - 1)microsporogenesis 2)megasporogenesis  Kingdom Fungi: 1. Characteristics:  Decomposers- bacteria and fungi  Heterotrophs (w/ extracellular digestion) -saprobes: nutrients from dead organic matter -symbionts: nutrients from living organic matter  Chitin=cell wall  Reproduce both asexually and sexually  Symbiotic relationships  Are more closely related to animals than to plants 2. General Morphology: A. Thallus/Mycelium-Body of the fungal organism -releases exoenzymes-externally released enzymes B. Hyphae- thread-like filaments..combined & form a network=mycelium -Septate: cell walls partition cells -Coenocytic: no cell wall partitions C. Haustoria-Specialized hyphae that release exoenzymes for extracellular digestion 3. Reproduction: A. Syngamy- fertilization occurs initially with the fusion of cytoplasm from two different cell types. (gametes coming together) B. Plasmogamy- fusion of cytoplasm C. Karyogamy- fusion of the haploid nuclei..creates a transition ploidy called (n+n) D. Heterokaryon/ Dikaryon- (n+n) the two haploid nuclei are from different individuals E. Spores (dispersion and survival) F. Classification G. Syngamy-->plasmogamy-->heterokaryotic stage-->karyogmay-->dikaryotic stage Ex. Notes: -fungi don’t start separating in mitosis until after plasmogamy -if spores reproduce sexually, spores wouldn’t be identical - Thallus (body) of a fungus is haploid - Sexual advantage= genetic variation..disadvantage= have to find a partner 4. Symbiotic Relationships:  Mutualism-Both organisms involved are benefited from the relationship  Mycorrhizae 

- most important association - between plant roots + fungi - the plant provides fungus with organic nutrients - fungus extends plants roots to reach more minerals for absorption  Lichens - between algae/cyanobacteria + fungi - Algae provide food - Fungi provide structural positioning for photosynthesis, decomposition & soil production  Crustose- “crust-like”, grow flat along trees and rocks  Fruiticose- “cup- or club-like”, branching& cylindrical appearance of the thallus, brightly colored  Foliose- “leaf-like”, golden/brown, grow vertically  Commensalism- One organism is benefited while the other organism is neither benefited nor harmed  Parasitism - one organism is benefited while the other organism (host) is harmed - ex. Athletes foot 5. Four major Phyla:  Phylum Zygomycota- “Zygote Fungi” I. Characteristics  Coenocytic (with few or no septa) hyphae  Terrestrial in nature- found in soil or decaying material  Spores dispersed by air  Rhizopus = black bread mold II. Reproduction  Sexual or asexual  Zygosporangia- fruiting body  Zygospores -sexual spores  Sporangiospores -asexual spores  Rhizoids- root-like hyphae for anchorage  Phylum Ascomycota- “Sac Fungi” I. Characteristics  Largest class of fungi  free-living & symbiotic  Spores dispersed by air  Septate hyphae w/ perforations  Aquatic/terrestrial in nature  Ascus forms Ascocarp= ploidy is (n+n)  Produce 4-8 haploid spores through meiosis  Peziza  Penicillium (antibiotic comes from)  Morela & Truffles  Saccharomyces (unicellular yeast)  Used in production of cheese, bread, and wine II. Reproduction

Sexual and asexual Ascocarp-fruiting body Takes on various forms Asci-sacs containing spores Ascospores- sexual spores Conidia- asexual spores Conidiophore -specialized stalks  Phylum Basidiomycota- “Club Fungi” I. Characteristics  Terrestrial in nature  Spores dispersed by air  Septate hyphae  Major decomposers of wood  Mushrooms  Toadstools  Puffballs  Bracket fungi  Humongous Fungus- worlds largest organism  Fairy rings -another form of ringworms II. Reproduction  ONLY SEXUAL  Basidiocarp -fruiting body  Basidia- specialized reproductive cell  Same as Ascomycota but with gills  Phylum Deuteromycota- “Imperfect Fungi” I. Characteristics/ Reproduction  Reproductive cycle not fully understood  Only reproduces ASEXUALLY  Produces asexual spores (conidia)  Terrestrial in nature  Athlete’s Foot  Ringworm- not a real worm, in humans  Molds Ex. Notes: -Bacteria keeps fungi in check / also compete against each other       ...