19_FungiW11 - Green Plants & Fungi • Slime Molds...

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Unformatted text preview: Green Plants & Fungi • Slime Molds • Fungi – Ecology – Mycorrhizae – Life cycle & major groups • Opisthokonts – Choanoflagellates – Animals Archaea AMOEBOZOA UNIKONTA Unikonts • Single Flagella – May not be true synapomorphy OPISTHOKONTA Fungi Choanoflagellates Animals PLANTAE • Triple gene fusion Red algae Green algae Land plants RHIZARIA Foraminifera CHROMALVEOLATA ALVEOLATA Dinoflagellates STRAMENOPILA Diatoms Brown algae Unikonts: Amoebozoans Lobe shaped pseudopodia Unikonts: Single flagella Engulf food Ameobozoans Fungi Choanoflagellates Opisthokonts: Flagella at rear of cell Animals Amoebozoans: Slime Molds • Slime Molds • Form “Supercells” – Large multinucleate a group of green algae; nucleus cells likeregulate different parts of multicell to the • Reproduction – Form fruiting bodies that undergo meiosis & form wind-borne spores – Spores germinate into haploid amoeba – Haploid amoeba fuse Fungi • Eukaryotes • Opisthokonts (flagella at rear of cell) • Absorb nutrients directly from the environment may not remain in all the decendensts or stages of life Fungal Morphology • Must maintain high SA/V Single cells: “yeasts” Mycelium (-ia)- multicellular Filaments or “hyphae”: 1 cell wide Fungal Ecology: Decomposers 1st mode of feeding method • “saprophytes” digest dead material • Break down lignin & cellulose – Use cellulose for energy – Only break down lignin to get to cellulose bread down lignin and get to the cellulose for nutrients and energy Laetiporus gilbertsonii Sulfur Shelf fungus “Tree Brain” fungus Thesneeze.com Fungal Ecology: Parasites feed on living things • Not major cause of disease in humans • Common disease in plants discoloration of the leaves – Also called smuts, rusts, mildew • Chestnut Blight introduced to N. America 1900 – Introduced toin No.almost extinct by 1940, american chestnut trees America in 1900 – By 1940 American Chestnut Trees almost extinct fungi infected ants => maintain diversity in the forest, prevent one group of organisms from growing too large Fungal Ecology: Mutualism • Mycorrhizae – Absorb nutrients in soil – Transfer them to plants – Increase root SA/V – Enzymes efficient at breaking down molecules to release nutrients Hygrocybe psittacina Green Parrot Toadstool Fungal Mutualism: Experiment Hypothesis (H1): Host plants provide mycorrhizal fungi with sugars, fungi provide plants with phosphorous or nitrogen from soil Null Hypothesis (H0): No exchange of sugars or nutrients large amonts of labeled Pand N found in plant Prediction H1: Labeled C transferred prediction (H1) labeled C present in both plant and fungi; to inmycorrhizae incarbon found in soil control, little control, little labeled treatment. In labeled carbon found in soil Prediction H0: No difference in carbon localization how to know if fungi is parasitic or mutualistic => the fitness of one party increased or both parties measure the seed production in the field Prediction H1: Labeled P or N more in the plant prediction (H1) labeled P or N found much transferred to plant in treatment. In control, little or no labeled N or P in plant Prediction H0: No difference in P or N localization Figure 31-9 isotope not commonly found Mycorrhizal Types • Ectomycorrhizae (EMF) – – – – cover root root Covertips cellstips do not penetrate temperate latitudes big coniferous forest Do not penetrate cells mostly in basidiomycota clade Temperate latitudes Mostly in Basidiomycota clade EMF Cross section of plant root Mycorrhizal Types • Arbuscular Mycorrhizae (AMF) – grow into rootinto roota cells parasitic relationship, might change from parasites to mutualists) Grow cells (more like mode of 80% of all pant species – 80% of all plant species – key in landin land transition Key transition common in tropical forest AMF Cross section of plant root Fungi: Taxa • Chytrids • Basiodiomycota (club fungi) • Ascomycota (lichen formers) Chytrid Fungi • Primarily aquatic • Mutualists in guts of mammal herbivores – Digest cellulose • Factor in global amphibian declines digest cellulose Chytrid Life Cycle Only fungi with alternation of generations. (a) Chytrids include the only fungi in which alternation of generations occurs. fusion SIS I TO M gametes form in gametangia MI TOSIS Gametes plasmogamy and karyogamy Zygote occur simultaneously Sporophytic mycelium Spores form in sporangia gametophytic mycellum (n) 1 mm Spore Haploid Diploid Fungal Reproduction & Life Cycle • Mycelium is haploid • Plasmogamy union of cells – – – – Cells of hyphae Nuclei do not fuse N+N cell (Not 2N) “heterokaryotic” • Karyogamy – Fusion of nuclei Amanita muscaria Basidiomycota (club fungi) • Includes fungi that produce mushrooms – Mushrooms produce spores • Basidia= cells where spores form • Saprophytes digest lignin only fungi that can – Only fungi that can digest lignin • Ectomycorrhizae (EMF) Basidiomycota Life Cycle karyogamy 2n Basidium Spores Spores form hyphae PLASMOGAMY IS TOS MI Hyphae of different mating types Haploid (n) Heterokaryotic (n + n) Diploid (2n) Figure 31-13d Ascomycota Soredia Asci produced by fungus • Ascus: cup-like reproductive structure • Includes – lichens:Symbiosis with cyanobacteria or green algae – Saprophytes – EMF – parasites (Cordyceps) • Human uses – Penicillin – Truffles – Wine & cheese Fungal layer Algal layer Fungal layer rock 1 cm Ascomycota: Life Cycle Spores form hyphae Spores Ascus 2n Dikaryotic mycelium Hyphae of different mating types make contact and fuse Haploid (n) Heterokaryotic (n + n) Diploid (2n) Figure 31-12 Animals: Phylogeny Unikonts: Single flagella Amoebozoans Fungi Choanoflagellates Opisthokonts: Flagella at rear of cell Animals Animals: Phylogeny Single celled ancestor, Resembled choanoflagellate Choanoflagellates Animals Synapomorphies: •Multicellular •Genetics, rRna •Epithelial tissue =“metazoa” or “Animalia” Multicellular animals Choanoflagellates Sponges Colony Choanoflagellate Sponge feeding cell cell (choanocyte) Interior Food particles Water current Water current Multicellular organism Figure 32-10 What Major Characters Define Animal Clades? • Tissue Layers – Epithelial Tissue – Diploblasty – Triploblasty • • • • • • Body symmetry – Radial vs bilateral Presence of Coelom Segmentation Embryology Genetics Other Animals Multicellularity Choanoflagellates Porifera Cnidaria Ctenophora Acoelomorpha LOPHOTROCHOZOA Rotifera Loss of coelom Platyhelminthes Segmentation Annelida Molluska ECDYSOZOA Nematoda ANIMALIA PROTOSTOMES Bilateral symmetry BILATERIA DEUTEROSTOMES Coelom, cephalization, CNS Arthropoda Segmentation DEUTEROSTOMES Echinodermata Segmentation Chordata • Epithelium Characters: Tissues – Tightly joined cells that cover surface • Diploblastic: Endoderm & Ectoderm • Triploblastic: Endo-, Ecto-, and Mesoderm Asymmetry Symmetry Radial symmetry Sponge No plane of symmetry Jellyfish Multiple planes of symmetry Bilateral symmetry Lizard Single plane of symmetry Posterior Anterior Figure 32-5 ...
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