What are fungi?

Eukaryotic heterotrophs that absorb nutrients they use hydraulic enzymes to digest compounds

Diverse roles

Decomposers Parasites Mutualists

Decomposers

Break down the nonliving

Parasites

take nutrients from living host

Mutualist

absorbing nutrients from host but also provide water

Fungal Body Structure

multicellular filaments single cell yeasts

multicellular fungi

form networks of tiny filaments called hyphae

hyphae

consist of tubular cell walls called chitin hyphae form branched networks called mycelia which adapt for absorption

Chitin

prevents the cell wall from bursting

mycelia

increase surface area for absorption

Mycorrhizal

mutually benefiting relationship between fungi and plant roots Fungi supplies water Plant provides nutrients Ex. Ectomycorrhizal and Arbuscular mycorrhizal

Reproduction

produce spores sexually and asexually

spore

seeds for fungi carried long distances germinate and form new mycelia

Sexual life cycle

Plasmogamy --> Heterokaryotic stage --> karyogamy --> meiosis --> produce haploid spores

Plasmogamy

cytoplasmic fusion

Karyogamy

nuclear fusion

Mucoromycetes

Include fast growing molds and mutualistic fungi (mycorrhizae) Typical life cycle: Rhizopus stolonifer

Rhizopus stolonifer

asexual reproduction mycelia form sporangia that produce identical haploid spores sexual reproduction neighboring mycelia form a zygosporangium: Karyogamy and meiosis occur

Ascomycetes

sac fungi - produce sac like asci (found in fruiting bodes called ascocarps) during sexual reproduction Ex. Bakers yeast, truffles. morels

fruiting bodies

visible portion of the fungi

Basidiomycetes

club fungi - produce basidiospores on a club shaped basidium (found on fruiting body called basidiocarps) Ex, puffballs, mushrooms, shelf fungi

Lichens

symbiotic associations between photosynthetic microorganisms (green algae or cyanobacteria) - fungus provides shelter and water - algae provide nutrients

3 main types of lichen

fruticose foliose crustose

Parasites in humans

ringworm athletes foot yeast infection