AP Biology Crosby High School Fungi AP Biology Crosby High School

Absorptive Nutrition Secretes Hydrolytic Coenzymes Types of absorption Saprobes Parasitic Mutualistic

Extensive Surface Area and Rapid Growth Hyphae: tiny filaments that make fungal body Tubular walls surrounding plasma membrane Mycelium: interwoven hyphae Septa: cross-wall divides Hyphae into cells Cell walls made of Chitin Coenocytic: Aseptate Haustoria: Hyphal tips that penetrate host tissue

Fungi Reproduction Can be asexual or sexual Produce spores that disperse Spores need a moist habitat to grow Puffballs Most fungi have heterokaryotic stages Most nuclei are haploid Heterokaryon: Fusion of two Hyphae

Sexual Life Cycle Heterokaryon Two nuclei exist in different parts of mycelium Nuclei may mingle and exchange genes Plasmogamy: Fusion of parental cytoplasm Karyogamy: Fusion of haploid nuclei Dikaryotic: Interim btwn. Plas. and Kary.

Phylum Chytridiomycota Mainly aquatic Saprobes Parasitic attack plant, protists and animals Originally classified under protists Absorptive Chitin cell walls Most form Coenocytic Hyphae Flagella suggest early origin

Phylum Zygomycota Mostly terrestrial Mycorrhizae: mutualist w/ plant roots Coenocytic w/ septa only at reproductive cells Rhizopus stolonifer (black bread mold) Asexual phase forms bulbs containing spores Reproduces sexually if conditions deteriorate Pilobolus: aims spores

Phylum Ascomycota Among most devastating plant pathogens Saprobes of plants ½ are mutualists w/ algae as lichens Spore production in Asci Many asexual spores at tips of Conidiophores Naked spores called Conidia

Heterokaryotic Stage Plasmogamy produces ascogonium Cells at tips develop into asci Karyogamy combines parental genomes and meiosis forms 4 ascospores Mitosis doubles ascospore number

Phylum Basidiomycota Basidium: Club Fungus (“Little Pedestal”) Decomposers of wood Mushrooms, shelf fungi, puffball, rusts and smuts Periodically produce Basidiocarps Asexual reproduction less common Mushrooms sprout in a few hours

Other Classifications Molds: Rapidly growing, asexual fungi Refer only to asexual spores early in life May become sexual as Zygosporangia, Ascocarp, or Basidiocarp Deuteromycetes (imperfect fungi) Yeasts: Unicellular fungi in moist env. Cellular division or budding Some rep. sexually: Ascomycota or Basidiomycota Saccharomyces cerevisiae

Other Classifications (cont.) Yeasts (cont.) Rhodotorula: shower curtains Candida: present in epithelial tissue Lichens Mutualistic w/ algae Algae provide food (cyanobacteria fixes Nitrogen) Fungus provides env. Water, minerals, gas exchange, protecttion Reproduce as asexual symbiont (Soredia) Mycorrhizae: Mutualistic plant roots and fungi

Ecological Impact Decompose and recycle elements Pathogens Claviceps purpurea Forms ergots on rye Lysergic acid causes Gangrene, nervous spasms, burning sensations, hallucinations, and temporary insanity Mycosis Ringworms Candida albicans Commercial use Many types of consumptions Penicillin comes from Penicillium

Lichen Structure

Basidiomycota

Basidiomycota Life Cycle

Fairy Ring

Ascomycota Life Cycle

Zygomycota Life Cycle

Fungi Structure