Contractile vacuole action

Amoeboid movement

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Chapter 31 ~ Fungi

It is as large as 1,665 football fields combined. It is 3.4 square miles in size and covers 2,200 acres of land in the Blue Mountains of eastern Oregon. Humongous Fungus Honey Mushroom Blankets Forest, Kills Trees

Fungi Heterotrophic by absorption (exoenzymes) Decomposers (saprobes), parasites, mutualistic symbionts (lichens) Hyphae: body filaments septate (cross walls) coenocytic (no cross walls) Mycelium: network of hyphae Chitin cell walls (polysaccharide) Nuclei Septate hypha Septum Pore Cell wall Nuclei Coenocytic hypha

LE 31-2 Reproductive structure Hyphae Spore-producing structures Mycelium 20 µm

Fungus Life Cycle Bread Mold Life cycle Most have 3 distinct phases: 1. Haploid (n) 2. Heterokaryotic (n + n) (think of Sordaria) 3. Diploid (2n) Asexual phases: (n spores, n clones) Sexual Phases: (n spores, w/ genetic variety) Plasmogamy (cytoplamic fusion) Dikaryotic (n + n) Karyogamy (nuclei fusion) Diploid (2n) Meiosis (spores n)

Haploid (n) Key Heterokaryotic (n + n)) Diploid (2n) PLASMOGAMY (fusion of cytoplasm) Heterokaryotic stage KARYOGAMY (fusion of nuclei) Mycelium SEXUAL REPRODUCTION Zygote Spores GERMINATION MEIOSIS Spore-producing structures ASEXUAL REPRODUCTION Spores GERMINATION Spore-producing structures

Fungi Diversity, I Phy: Chytridiomycota aquatic fungi; chytrids lineage closest to protists (flagella) Phy: ZygomycotaRhizopus (food mold) mycorrhizae: mutualistic with plant roots zygosporangia: resistant structure (freezing and drying)

Fungi Diversity, II Phy.: Ascomycota sac fungi yeasts, truffles, morels, Sordaria asci: sexual spores conidia: asexual spores Phy.: Basidiomycota club fungus mushrooms, puffballs, shelf fungus, rusts basidiocarps: produce sexual spores

Specialized Lifestyles, I Molds only the asexual stage (asexual spores)Penicillium (antibiotic, cheese) Yeasts unicellular, asexual buddingSaccharomyces (bread, alcohol)

Specialized Lifestyles, II Lichens symbiotic association held in a hyphae mesh alga provides food, fungus provides physical environment pioneer organisms air pollution detection Mycorrhizae root and fungi mutualism found in 95% of vascular plants exchange of organic minerals increases absorptive surface of roots