Unit 6--Microbiology Chapter 21 Fungi

Fungal Characteristics Filamentous bodies: Hyphae = thin filaments Mycelium = entire mass of hyphae Chitinous cell walls (instead of cellulose)

Fungal “invasion” in leaf

Fungal characteristics How they obtain food: 1) Secrete digestive enzymes into environment 2) Digestion takes place outside their body 3) They absorb what they need, leaving the rest Why is this an advantage ? (to the rest of the world) (Compost)

Fungal characteristics Reproduction: 1) Asexually (usually used when times are good with plenty of food available) –Haploid spores produced in large numbers 2) Sexually (usually used when times are harsh) –Haploid gametes fuse to form a zygote that can survive hard times

Phylum…examples… types of reproduction Zygomycota (Zygote-producing fungus) Rhizopus (black bread mold) Asexual with sporangia Sexual with zygospores

Phylum…examples… types of reproduction Zygomycota (Zygote-producing fungus) Rhizopus (black bread mold) Asexual with sporangia Sexual with zygospores

Sporangia can produce 50,000 spores Formed when 2 gametes unite to form a zygote that in enveloped by a zygospore which survives harsh times

Rhizopus 2,990 x

Phylum…examples… types of reproduction Ascomycota (cup fungus) Ex: yeast, truffles, & many other molds Asexual with conidia Sexual with ascus (sac-like spore case) inside a cup ($900 per pound!)

Aspergillus conidia Asci (with 8 spores) making up the “cup”

Phylum…examples… types of reproduction Basidiomycota… club fungus Ex: mushrooms, toadstools, puffballs, & bracket fungus Asexual is rare Sexual is club-shaped spore case called basidium

4X 10X 40X

Phylum…examples… types of reproduction Deuteromycota…imperfect fungus Ex: ringworm, athlete’s foot, penicillium mold Asexual only No known sexual stage

Other relatives Lichens: Symbiotic fungus & algae Fungus provides “home,” algae provides “food”

Mycorrhizae:Mycorrhizae: Symbiotic fungus & plant root cellsSymbiotic fungus & plant root cells Root cells provide “home”Root cells provide “home” fungus provides mineral transportfungus provides mineral transport