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Chytridiomycota
- -only true fungi to be aquatic
- -they move by a posterior flagellum called 'zoospores'
- -some are hyphal, others are unicellular
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Chytridiomycota
-Allomyces
- -saprophytic chytrid
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Chytridiomycota
-Reproduction
- Produce haploid gametes in sexual reproduction ordiplod zoospores in asexual reproduction
- -Gametes are for reproduction
- -Zoospores are for colonization
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Zygomycota
- -terrestrial
- -hyphael: grow as threads, hyphae are coenocytic (lack septa)
- -nuclei are haploid
- -primarily saprophytes
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Zygomycota
-Reproduction
- -nuclei are haploid
- -reproduce by asexual spores contained in the sporangium
- -sexual reproduction can occur by the fusion of isomorphic (different mating types) multinucleate gametangium
- - the product is zygosporangia which undergo meiosis
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Zygomycota
-Examples
-Rhizopis: common black bread mold, sporangiospores are supported by rhizoid structures like roots
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Conidial Fungi
- -includes fungi whose form of sexual reproduction is not known
- -asexual spores (conidia) are not protected by a cover, but are produced as chains of cells which are then severed at the tips of specialized hyphae (conidiospores)
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Conidial Fungi
-Types
- -Penicillium
- -Aspergillus
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Ascomycota- 'sac' fungi
- -have septate hyphae or grow as yeasts
- -all sexual spores are made in the ascus
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Ascomycota
-Reproduction
- -gametangia arise as special hyphael branches; the 'male' (Antheridium) and 'female' (Ascogonium)
- -the 'female' had a receptive hair-like projection called a trichogyne
- -nuclei is passed from M to F when the antheridium touches the trichogyne
- -ascogenous occurs (formation of a new ascus) whereby the ascus contains nuclei from each parents
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Ascomycota
-Ascocarp types
- -a) perithecium
- -b) apothecium
- -c) cleistothecium
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Ascomycota
-Ascus
- -following the formation of asci in the dikaryotic cells, fertilization occurs
- -meiosis takes place immediately forming 4 haploid nuclei
- -these four nuclei then divide again by mitosis
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Basidiomycota- the 'club' fungi
- -have septate hyphae
- -many are saprophytes or mycorrihizal
- -all sexual spores (Basidiospores) are born externally on the basidium (club)
- -have no distinct gamatangia
- -many club fungi form macroscopic basidiocarps
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Basidiomycota
-Reproduction
- -asexual reproduction involves conidia
- -fusion of hyphae occurs early and the organism exists dikaryotically for most of its life
- -the dikaryotic mycelium eventually forms young basidia
- -the two nuclei of the basidium unite (karyognamy) and form a diplod nucleus
- -meiosis occurs and the haploid nuclei form basidiospores
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Lichens
- -organisms made up of fungi and green algae or cyanonacteria
- -growth conditions are usually poor
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Heterotrophic Protists
a. Plasmodial Slime molds
- -plasmodium is a mass of multinecleate cytoplasm capable of creeping on solid surface
- -if conditions are unfavorable, the plasmodium will enter the resting stage, forming a sclerotium
- -are eukaryotic heterotrophs with two stages
- 1) vegetative (feeding) stage
- - are amoeboid or flagellated
- 2) reproductive stage
- -form spores with rigid walls, often containing cellulose
- -spores are carried by teh wind
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Heterotrophic Protists
b. Oomycetes
- - absorptive heterotrophs
- -cell walls contain cellulose
- -have coenocytic hyphae
- -aquatic (require water for reproduction)
- -zoospores have two flagella: whiplash and tensile
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Heterotrophic Protists
b. Oomycetes- Reproduction
-zygote forms a thick wall and becomes a restings pore
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