AP Biology Lecture #48 Protists

Kingdom Fungi The characteristics of fungi The characteristics of fungi The evolution of the fungi The evolution of the fungi Fungal classification Fungal classification Fungal life styles Fungal life styles All photographsin this presentation © Pearson Education or Fred M. Rhoades

The Characteristics of Fungi Fungi are NOT plants Hyphae = tubular units of construction Heterotrophic by absorption Reproduce by spores Ecologically pivotal roles

Hyphae Tubular Hard wall of chitin Crosswalls may form compartments (± cells) Multinucleate Grow at tips

Heterotrophic by Absorption Fungi get carbon from organic sources Hyphal tips release enzymes Enzymatic breakdown of substrate Products diffuse back into hyphae Product diffuses back into hypha and is used Nucleus hangs back and “directs”

Modifications of hyphae Fig 30.2 (don’t worry about the terms)

Hyphal growth Hyphae grow from their tips Mycelium = extensive, feeding web of hyphae Mycelia are the ecologically active bodies of fungi This wall is rigidOnly the tip wall is plastic and stretches Video of time lapse growth in a Zygomycote, Phycomyces

Reproduce by spores Spores are reproductive cells – Sexual – Asexual Formed: – Directly on hyphae – Inside sporangia – Fruiting bodies Amanita fruiting body Pilobolus sporangia Penicillium hyphae

Figure 18.12A Fungal mycelia and hyphae 18-9

Hyphal growth from spore mycelium germinating spore Mycelia have a huge surface area

Fig 31.1 mycelium fruiting bodies both are composed of hyphae

Fungal Ecology Saprobes – Decomposers – Mostly of plants, some animals Parasites – Harm host – Mostly on plants, some animals Mutualists – Lichens – Mycorrhizas – Others

Fig 28.8 Evolution of the fungi

Classification & Phylogeny motile spores zygosporangia asci basidia Fig 31.4

Chytridiomycota – “chytrids” Simple fungi Produce motile spores Mostly saprobes and parasites in aquatic habitats Could just as well be Protists Fig 31.5 Chytridium growing on spores

Zygomycota – “zygote fungi” Sex - zygosporangia Asex - common Hyphae have no cross walls Grow rapidly Mycorrhizas Fig 31.6 Rhizopus on strawberries

Fig 31.7 Life cycle of Rhizopus You are not responsible for this life cycle Life cycle is predominantly haploid Asexual sporangium with spores inside Sexual zygsporangium with one zygospore

Ascomycota – “sac fungi” Sex. – asci Asex. – common Cup fungi, morels, truffles Important plant parasites & saprobes Yeast - Saccharomyces Most lichens A cluster of asci with spores inside

Sac fungi diversity Note general comments about habitats and roles Enjoy looking at some amazing organisms This smaller-sized PPT file lacks diversity slides

Basidiomycota – “club fungi” Sex – basidia Asex – not so common Long-lived dikaryotic mycelia Rusts & smuts – primitive plant parasites Mushrooms, polypores, puffballs Enzymes decompose wood Mycorrhizas SEM of basidia and spores

Mushroom Life Cycle Fig Nuclear fusion in basidium Meiosis Hyphal fusion of haploid mycelia haploid mycelium young basidia - the only diploid cells mycelium and fruiting body are dikaryotic N 2N N+N

Club fungi diversity Check out Taylor Lockwoods, “Treasures from the Kingdom Fungi”! Check out Taylor Lockwoods, “Treasures from the Kingdom Fungi”! This smaller-sized PPT file lacks diversity slides

A rust growing on a currant leaf 0.5 cm Yeasts Molds Mycorrhizas Lichens

Yeasts Single celled fungi Adapted to liquids – Plant saps – Water films – Moist animal tissues Candida Saccharomyces

Schizosaccharomyces octospora – fermenter of Palm Wine 10 μm

Molds Rapidly growth Asexual spores Many human importances – Food spoilage – Food products – Antibiotics, etc. Fig Antibiotic activity Noble Rot - Botrytis

Mycorrhizas “Fungus roots” Mutualism between: – Fungus (nutrient & water uptake for plant) – Plant (carbohydrate for fungus) Several kinds – Zygomycota – hyphae invade root cells – Ascomycota & Basidiomycota – hyphae invade root but don’t penetrate cells Extremely important ecological role of fungi!

“Ecto”mycorrhizas Russula mushroom mycorrhizas on Western Hemlock root Fungal hyphae around root and between cells Mycorrhiza cross sections

Lichens “Mutualism” between – Fungus – structure – Alga or cyanobacterium – provides food Form a thallus – Foliose – Fruticose – Crustose Fig 31.16

Lichen internal structure Fig Lobaria

Lichens as biomonitors Thalli act like sponges Some species more sensitive Which species are present can indicate air quality (Most resistant species can also be analyzed for pollutants) Northwest Air Net Project – Species chart Species chart – Table of sensitivities Table of sensitivities

Lichen diversity Check out my 3-D cryptogam site! Check out my 3-D cryptogam site More pictures of: – Lichens – Mushrooms – Bryophytes – Slime molds This smaller-sized PPT file lacks diversity slides