FUNGI

Largest organism in the world is a fungus It occupies 2,384 acres (965 hectares) of soil in Oregon's Blue Mountains. This humongous fungus would encompass 1,665 football fields, or nearly four square miles (10 square kilometers) of turf. ~2,500 + years old Honey mushrooms Parasite of conifers

Fungi were the first land organisms probably as lichens. Fungi were the largest land organisms at the time of the Bryophytes; giant fungi up to 9 meters tall. Prototaxites sporophytes Possibly a lichen?

reported to infect humans. Over 600 fungal species reported to infect humans. Ringworm

Kingdom Fungi (Eukaryotic, multicellular, heterotrophic organisms, feeding by external digestion) Rigid cell walls of chitin or cellulose Hyphae = tubular thread-like cells Mycelium = mat-like network of hyphae

Four Major Groups of Fungi 1) Chytridiomycota --simplest fungi & with flagellated cells in the life cycle Previously grouped with the Protista

Skin parasites on amphibians & causing their world-wide decline.

Four Major Groups of Fungi 1) Chytridiomycota Note: both male & female gametes have flagella & so do the zygote & the spores!

Four Major Groups of Fungi 2) Zygomycota Bread Mold fungus

Four Major Groups of Fungi 2) Zygomycota

Four Major Groups of Fungi 3) Ascomycota (= sac fungi; produce spores in sacs= asci) Cup fungi

Penicillium fungus

Four Major Groups of Fungi 3) Ascomycota e.g. Yeast C6H12O6 2CH3CH20H + CO2 + ATP Sugar Ethyl alcohol

Four Major Groups of Fungi 3) Ascomycota (= sac fungi; produce spores in sacs= asci) e.g. Morel Ascomycota produce the “earthy” smell of soil

Four Major Groups of Fungi 3) Ascomycota e.g. truffles (Underground fungi)

Truffles The record price paid for a single white truffle was set in December 2007, when Macau casino owner Stanley Ho paid $330,000 (£165,000) for a specimen weighing 1.5kg (3.3lb), discovered by Luciano Savini and his dog Rocco

Four Major Groups of Fungi 4) Basidiomycota (= club fungi; produce spores in club-shaped structures= basidia)

Four Major Groups of Fungi 4) Basidiomycota (= club fungi; produce spores in club-shaped structures= basidia)

Four Major Groups of Fungi 4) Basidiomycota

Four Major Groups of Fungi 4) Basidiomycota Polypores

Four Major Groups of Fungi 4) Basidiomycota Coral Fungus

Types of Nutrition in Fungi Heterotrophic 1) Parasitic (e.g. athlete’s foot, ring worm, jock itch; Chestnut Blight; Potato Blight) 2) Predators (150 species of fungi trap and digest soil nematodes using adhesive knobs or loops) 3) Saprotrophic (= decomposers consuming dead organisms by external digestion) 4) Mutualistic (e.g. ants & “fungal farming,” lichens & mycorrhizae)

Fungi as Parasites Bat White Nose Syndrome

Fungi as Predators Nematode Trapping Fungi

Fungi as Saprotrophs (Decomposers)

Fungi as Mutualists Lichens

Algae (often green algae) + fungi Fungus Algae Fungus Fungus Often yeasts are part of the symbiosis, meaning 2 fungi are involved.

Mycorrhizae = Symbiotic fungi living within the root system of plants. 80% of plant species depend on mycorrhizae They gain photosynthetic products from plants They greatly increase the surface area of roots (10-1000 times) & increase the uptake of water & minerals (especially nitrogen & phosphorous). The fungi take in plant carbohydrates in exchange. 20% of photosynthesis can go to mycorrhizae

Mycorrhizae

Mycorrhizae

Many plant partners The fungal network allows plants to exchange nutrients. Resource sharing by fungal networks. More than 400 plants parasitize the system. They lack chlorophyll and don’t photosynthesize but rely on carbon from the mycorrhizae. (e.g. some orchids)

Two Types of Mycorrhizae Glomeromycota

Different Reproductive Structures of the Phyla of Fungi

Fungus Evolution Dikarya (n + n) Glomeromycota Basidiomycota Ascomycota Chytridiomycota Zygomycota Dikarya (n + n) Flagellated protozoan

Fungus Evolution 400 mya Earliest fungal fossil 1.2 BYA Basidiomycota Ascomycota Glomeromycota Chytridiomycota Zygomycota 400 mya Colonized land long before plants Earliest fungal fossil 1.2 BYA Flagellated protozoan

Where would you place the Ascomycota? Flagellates B C A B C D E D E 1

Next Lecture: ANIMALS & THE CAMBRIAN EXPLOSION