Fig. 31-1Honey Mushroom, Oregon, subterranean filaments =1,800 football fields

Ch. 31 Fungi

Characteristics of Fungi

• Multicellular Eukaryotes with few unicellular

• Heterotrophic by absorption

• Mostly decomposers but some parasites, mutualists, even predator

• Diverse habitats

Fig. 31-4a

(a) Hyphae adapted for trapping and killing prey

NematodeHyphae

25 µm

Fig. 31-2

Reproductive structure

Spore-producingstructures

Hyphae

Mycelium = condensed network of hyphae

20 µm

Structures

Fig. 31-3

(b) Coenocytic hypha

Septum

(a) Septate hypha

Pore

Nuclei

Nuclei Cell wallCell wall

Fig. 31-5-3

Spores

Spore-producingstructures

GERMINATION

ASEXUALREPRODUCTION

Mycelium

Key

Heterokaryotic(unfused nuclei fromdifferent parents)

Haploid (n)

Diploid (2n)

SEXUALREPRODUCTION

KARYOGAMY(fusion of nuclei)

PLASMOGAMY(fusion of cytoplasm)

Heterokaryoticstage

Zygote

Spores

GERMINATION

MEIOSIS

Reproduction varies & is specificanimation

Fig. 31-6

2.5 µm

Penicillium, asexual structures called conidia

Fig. 31-7

10 µm

Parentcell

Bud

Yeast reproduce asexually via budding

Fig. 31-8

Animals (and their closeprotistan relatives)

Other fungi

Nucleariids

Chytrids

UNICELLULAR,FLAGELLATEDANCESTOR

Fu

ng

i

Op

istho

kon

tsOrigin of Fungi is unicellular flagellated protist. Fungi are more closely related to animals than to plants that descended from algae.

Fig. 31-UN1

Chytrids

Basidiomycetes = club shaped

Zygomycetes = sphere shaped

Glomeromycetes

Ascomycetes = sac shaped

3 of 5 Fungi phyla are defined by fruiting body structure

Fig. 31-UN6

Fig. 31-11b

Zygomycetes (1,000 species)

Bread Mold and other fungi that rot food are included with sphere shaped fruiting bodies called zygosporangia that hold spores.

Fig. 31-UN6b

Fig. 31-13-4

Rhizopusgrowingon bread

SEXUALREPRODUCTION

Youngzygosporangium(heterokaryotic)

Gametangia withhaploid nucleiMating

type (–)

Matingtype (+)

Diploid (2n)

Haploid (n)Heterokaryotic (n + n)

PLASMOGAMY

Key

Diploidnuclei

Zygosporangium

100 µm

KARYOGAMY

MEIOSIS

Sporangium

Spores

Dispersal andgermination

ASEXUALREPRODUCTION

Dispersal andgermination

Sporangia

Mycelium50 µm

Fig. 31-14

0.5 mmNote zygosporangia fruiting bodies

Fig. 31-11d

Ascomycetes (65,000 species)

Cup fungi, morels and truffles are examples that hold spores in sac-like fruiting bodies called asci.

Fig. 31-UN6d

Fig. 31-16a

Morchella esculenta,the tasty morel

Fig. 31-16b

Tuber melanosporum, a truffle

Fig. 31-17-4

Key

Haploid (n)

Diploid (2n)Dikaryotic (n + n)

Conidiophore

Mycelium

ASEXUALREPRODUCTION

Germination

Hypha PLASMOGAMY

Haploid spores (conidia)

Conidia;mating type (–)

Matingtype (+)

SEXUALREPRODUCTION

Dikaryotichyphae

Ascus(dikaryotic)

Mycelia

KARYOGAMY

Diploid nucleus(zygote)

Germination

Asci

Dispersal

Dispersal

AscocarpEightascospores

Fourhaploidnuclei MEIOSIS

Fig. 31-11e

Basidiomycetes (30,000 species)

“Grocery store” mushrooms as well as shelf fungi, puffballs and fairy rings have fruiting bodies shaped like pedestals or clubs called basidia.

Fig. 31-UN6e

Fig. 31-18a

Maiden veil fungus(Dictyphora), afungus with an odor like rotting meat

Fig. 31-18b

Puffballs emittingspores

Fig. 31-18cShelf fungi, importantdecomposers of wood

Fig. 31-20

Fairy Ring – underground mycellium can grow 30 cm / yr. so giant rings are centuries old

Basidium

Fig. 31-19-4

SEXUALREPRODUCTION

Diploid (2n)

Haploid (n)Dikaryotic (n +n)

Key

PLASMOGAMY

Matingtype (+)

Haploid myceliaDikaryotic mycelium

Matingtype (–)

Basidia(n+n)

Gills linedwith basidia

Basidiocarp(n+n)

KARYOGAMY

Diploidnuclei

MEIOSIS

Basidium containingfour haploid nuclei

Dispersal andgermination

Basidiospores(n)

Basidium withfour basidiospores

Basidiospore1 µm

Haploid mycelia

Fungi Play Key Roles

• Nutrient cycling as decomposers (even jet fuel and house paint)

• Mutualistic relationship (so both benefit)– w/ plants & is called mycchorhizae– w/ animals usually to aide in digestion– w/ algae or cyanobacteria called lichen

• Pathogenic – disease causing– i.e. wheat rust & corn smut.

Fig. 31-22

Ants need fungi so they can digest leaves

Fig. 31-23

 A foliose(leaflike)lichen

A fruticose (shrublike) lichen

 Crustose(encrusting)lichens

> 13,500 lichen species exist

Fig. 31-24

Algal cell

Ascocarp of fungusSoredia

Fungal hyphae

Fungalhyphae Algal

layer

20 µ

mIn lichen the alga contributes food and the fungus provides shade, moisture, minerals even toxins so alga is not eaten.

Fig. 31-25

(c) Ergots on rye(a) Corn smut on corn (b) Tar spot fungus on maple leaves

Pathogenic Fungi may be killed with fungicides

Fig. 31-26

Staphylococcus

Zone ofinhibitedgrowth

Penicillium

Practical Uses of Fungi

• Food production – i.e. cheeses• Food• Fermentation – i.e. yeast• Medical Value - to produce antibiotics &

other drugs• GMO to produce enzymes that genetically

modified E. coli can not produce• Yeast as a research specimen since easy to

culture and to manipulate