Fungi

Ch.26

Fungi Importance

Recycle nutrients by decomposition

Fungi

EukaryoticHeterotrophs (external digestion,

decomposers or parasites)Cell walls of chitin All multi-celled (except yeast)

Fungi Structure

Hyphae - thin filaments with nuclei

Mycelium - hyphae tangled together (absorbs food)

Fruiting body - reproductive structure growing out of mycelium (like mushroom cap)

Fungus Reproduction

AsexualFragmentation: hyphae break off and grow on

their ownBudding: pinches off to produce offspring

Spore production: (reproductive cell that undergoes mitosis to produce new organism)

(Sporangiophores, sporangium, and sporangiospores)

Sexual Reproduction

Fungi are neither male or female have mating types [(plus (+) & a minus (-)]

Gametes =“plus (+) & minus (-)” to form zygote

Fungus Classification

1. Common Molds (Zygomycota)2. Sac Fungi (Ascomycota)3. Club Fungi (Basidiomycota)4. Imperfect Fungi (Deuteromycota)

Common Molds

Contain zygospores (spore with zygotes)

Rootlike hyphae called rhizoids (digestive enzymes)

Stolons – grow across the surfaceConjugation

Exs: Black bread mold, molds on meats & cheeses, etc.

Sac Fungi (Ascomycota)

ParasitesTiny spores = conidiaSexual = hyphae of two different

mating types - produces cuplike structures called ascocarp

Ascocarp contains sacs called asci that produces ascospores

Exs: Cup fungi, yeastYeast - reproduce thru budding

(asexual)

Club Fungi (Basidiomycota)

Produce small club-like structures = basidia

Spore-bearing structure = basidiocarp (cup & stalk)

Under cap = rows of “gills” lined with thousands of basidia

Basidia unite = zygote and develop into basidiospores

Exs: shelf fungi, puffballs, earthstars, jelly fungi, rusts (plant parasite), mushrooms

Club Fungi

Imperfect Fungi (Deuteromycota)

No sexual phase in life cycle

Exs: Penicillin

Symbiosis (Mutualism)

Both benefit1. Lichens2. Mycorrhiza

Lichens

Fungus & algae or cyanobacteria

Resistant to drought, cold Algae/Bact. provide energy

thru photo. & fungus provides water/minerals

First organisms on barren land Great indicator of air pollution

Mycorrhizae

Plant roots & fungi mycelia underground

80% of plants form mychorrhizae w/ fungi

Fungus helps provide water/minerals to plant

Plants give fungus energy from photosynthesis

Some plants won’t survive w/out these

Human Use

Production of B2, cortisone, penicillin, and other antibiotics, etc.

Production of cheeses, bread, beer, wines, and soy products

Fungal Diseases

Human, animal, plant Plant: corn smut, mildew, wheat rustHuman: Athlete’s foot, Ringworm, yeast

infectionsAnimal: Cordyceps (kills grasshoppers)

Fungal Diseases