Fig. 31-1
Honey
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
Nematode
Hyphae
(a) Hyphae adapted for trapping and killing prey
25 µm
Fig. 31-2
Structures
Reproductive structure
Hyphae
Spore-producing
structures
20 µm
Mycelium = condensed network of hyphae
Fig. 31-3
Cell wall
Cell wall
Nuclei
Pore
Septum
(a) Septate hypha
Nuclei
(b) Coenocytic hypha
Fig. 31-5-3
Key
Haploid (n)
Heterokaryotic
(unfused nuclei from
different parents)
Heterokaryotic
stage
PLASMOGAMY
(fusion of cytoplasm)
Diploid (2n)
KARYOGAMY
(fusion of nuclei)
Spore-producing
structures
Zygote
Spores
Mycelium
ASEXUAL
REPRODUCTION
SEXUAL
REPRODUCTION
MEIOSIS
GERMINATION
GERMINATION
Reproduction varies & is specific
Spores
animation
Fig. 31-6
Penicillium, asexual structures
called conidia
2.5 µm
Fig. 31-7
Yeast reproduce asexually via budding
Parent
cell
Bud
10 µm
Fig. 31-8
Origin of Fungi is unicellular flagellated protist. Fungi are more
closely related to animals than to plants that descended from algae.
Animals (and their close
protistan relatives)
Nucleariids
Chytrids
Other fungi
Opisthokonts
UNICELLULAR,
FLAGELLATED
ANCESTOR
Fig. 31-UN1
3 of 5 Fungi phyla are defined by fruiting body structure
Chytrids
Zygomycetes = sphere shaped
Glomeromycetes
Ascomycetes = sac shaped
Basidiomycetes = club shaped
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
Key
Haploid (n)
Heterokaryotic (n + n)
Diploid (2n)
PLASMOGAMY
Mating
type (+)
Mating
type (–)
Gametangia with
haploid nuclei
100 µm
Young
zygosporangium
(heterokaryotic)
Rhizopus
growing
on bread
SEXUAL
REPRODUCTION
Dispersal and
germination
Sporangia
Zygosporangium
KARYOGAMY
Spores
Sporangium
ASEXUAL
REPRODUCTION
MEIOSIS
Dispersal and
germination
50 µm
Mycelium
Diploid
nuclei
Fig. 31-14
Note zygosporangia fruiting bodies
0.5 mm
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
Conidia;
mating type (–)
Haploid spores (conidia)
Dispersal
Haploid (n)
Dikaryotic (n + n)
Diploid (2n)
Germination
ASEXUAL
REPRODUCTION
Key
Mating
type (+)
Hypha
PLASMOGAMY
Ascus
(dikaryotic)
Conidiophore
Dikaryotic
hyphae
Mycelia
Mycelium
Germination
Dispersal
Ascocarp
Asci
SEXUAL
REPRODUCTION
KARYOGAMY
Diploid nucleus
(zygote)
Eight
ascospores
Four
haploid
nuclei
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), a
fungus with an odor
like rotting meat
Fig. 31-18b
Puffballs emitting
spores
Fig. 31-18c
Shelf fungi, important
decomposers of wood
Fig. 31-20
Fairy Ring – underground mycellium can grow 30 cm / yr. so giant
rings are centuries old
Fig. 31-19-4
Dikaryotic mycelium
PLASMOGAMY
Haploid mycelia
Mating
type (–)
Haploid
mycelia
Mating
type (+)
Gills lined
with basidia
SEXUAL
REPRODUCTION
Basidiocarp
(n+n)
Dispersal and
germination
Basidiospores
(n)
Basidium with
four basidiospores
Basidium
Basidia
(n+n)
Basidium containing
four haploid nuclei
KARYOGAMY
MEIOSIS
Key
1 µm
Basidiospore
Diploid
nuclei
Haploid (n)
Dikaryotic (n+n)
Diploid (2n)
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
> 13,500 lichen species exist
A fruticose (shrublike) lichen
Crustose
(encrusting)
lichens
A foliose
(leaflike)
lichen
Fig. 31-24
In lichen the alga
contributes food
and the fungus
provides shade,
moisture,
minerals even
toxins so alga is
not eaten.
Ascocarp of fungus
Fungal
hyphae Algal
layer
Algal cell
Fungal hyphae
Soredia
Fig. 31-25
Pathogenic Fungi may be killed with fungicides
(a) Corn smut on corn
(b) Tar spot fungus on
maple leaves
(c) Ergots on rye
Fig. 31-26
Staphylococcus
Penicillium
Zone of
inhibited
growth
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