Fungi

  1. Nutritional Strategies (extracellular digestion, saprophytic, parasitic, mutualistic - lichens and mycorrhizae)

  • Extracellular Digestion: Hyphae secrete hydrolytic enzymes onto food → catabolic reaction, Nutrients are absorbed, Mycelium = high surface area to volume ratio

  • Saprophytic: feed on nonliving organic matter (decomposers)

  • Parasitic: feed on and live inside of a host organism (+/-)

  • Mutualistic: live with and share resources with another organism (+/+) 

  • Lichens: fungus + algae/photosynthetic bacteria

  • Mycorrhizae: fungus + plant roots 

  1. Parts of a Fungus (chitin, hyphae - septate vs. coenocytic, mycelium, fruiting body)

  • Cell wall made of chitin

  • Multicellular fungi have cells arranged in strings called Hyphae:  2 types: Septate: cells are divided by septum and have pores (allows for exchange of resources), Coenocytic: no septa between cells

  • Mycellium: Netlike body of a fungus made of hyphae (very large)

  • Fruiting Body: Reproductive structures produced by most multicellular fungi (the part we actually see of fungi) 

  1. Dimorphic Fungi

  • Have different body forms, (often yeast or mold) based on environmental conditions 

  • Plasmogamy: haploid cells from two mycelia fuse to form a cell with two nuclei 

  • Karyogamy: nuclei fuse to form a diploid zygote, zygote goes through meiosis to produce haploid spores, Fungi can only reproduce with other mating types, 

  1. Know how spores are dispersed.

  • Air currents, moving water, animals, fruitng body forms help with spore dispersal

    Mycelium: anchor the fungus, absorb water, digest organic nutrients

    Spore: Reproductive unit of fungus

    Cap: Support and protection 

    Gills: produce and release spores

    Stipe: elevate the store-bearing cap above the ground

    Annulus: remnant of partial veil that protected the immature gills

    Volva: Remnant of veil that entirely enclosed the mushroom

    Scale: Markers for mushroom identification, remnants of veil 

  • Secondary Metabolites: organic compounds produced by organisms that raise their fitness but are not essential (ex: antibiotics)

  • Bio Remdiation: using decomposers to breakdown pollution/wastes