1. Multicellular Fungus: hyphae …
Reproductive structure
Hyphae
Spore-producing
structures
Figure 31.2 Structure of a multicellular fungus
20 µm
Mycelium

2. Cell wall Cell wall Nuclei Pore Septum Nuclei (a) Septate hypha
Two forms of hyphae
Cell wall
Cell wall
Nuclei
Pore
Septum
Nuclei
Figure 31.3 Two forms of hyphae
(a) Septate hypha
(b) Coenocytic hypha

3. Fungus - have specialized hyphae
Nematode
25 µm
(a) Hyphae adapted for trapping and killing prey
Plant
cell
wall
Fungal hypha
Figure 31.4 Specialized hyphae
Plant cell
Plant cell
plasma
membrane
Haustorium
(b) Haustoria - penetrate cell walls of plants ++ or +-

4. Life Cycle of Fungi PLASMOGAMY KARYOGAMY Haploid (n) Heterokaryotic
Key
Haploid (n)
Heterokaryotic
stage
Heterokaryotic
(unfused nuclei from
different parents)
PLASMOGAMY
(fusion of cytoplasm)
Diploid (2n)
KARYOGAMY
(fusion of nuclei)
Spore-producing
structures
Zygote 2n
SEXUAL
REPRODUCTION
Spores
ASEXUAL
REPRODUCTION
Mycelium
Figure 31.5 Generalized life cycle of fungi
MEIOSIS
GERMINATION
GERMINATION
Spores

5. Penicillium: a mold that decomposes food
Penicillium: a mold that decomposes food Mold produce spores asexually by mitosis.
2.5 µm
Figure 31.6 Penicillium, a mold commonly encountered as a decomposer of food

6. The yeast Saccharomyces cerevisiae in several stages of asexual reproduction by budding.
Parent
cell
Figure 31.7 The yeast Saccharomyces cerevisiae in several stages of budding (SEM)
Bud

7. Fungi and their close relatives
Animals (and their close
protistan relatives)
UNICELLULAR,
FLAGELLATED
ANCESTOR
Nucleariids
Opisthokonts
Chytrids
Figure 31.8 Fungi and their close relatives
Fungi
Other fungi

8. Fungus Diversity Figure 31.11 Fungal diversity Hyphae 25 µm
Chytrids (1,000 species)
Zygomycetes (1,000 species)
Fungal hypha
Glomeromycetes (160 species)
Ascomycetes (65,000 species)
Figure Fungal diversity
Basidiomycetes (30,000 species)

9. Life Cycle of the zygomycete Rhizopus black bread mold
Key
Haploid (n)
Heterokaryotic (n + n)
Diploid (2n)
PLASMOGAMY
Mating
type (+)
Gametangia with
haploid nuclei
Mating
type (–)
100 µm
Young
zygosporangium
(heterokaryotic)
Rhizopus
growing
on bread
SEXUAL
REPRODUCTION
Dispersal and
germination
Zygosporangium
Sporangia
KARYOGAMY
Figure The life cycle of the zygomycete Rhizopus stolonifer (black bread mold)
Spores
Diploid
nuclei
Sporangium
ASEXUAL
REPRODUCTION
MEIOSIS
Dispersal and
germination
50 µm
Mycelium

10. Some zygomycetes, such as Pilobolus, can actually “aim” their sporangia toward conditions associated with good food sources.
Figure Pilobolus aiming its sporangia
0.5 mm

11. Ascomycetes - sac fungi
Morchella esculenta,
the tasty morel
Tuber melanosporum, a truffle
Figure Ascomycetes (sac fungi)

12. The life cycle of Neurospora, an ascomycete
Conidia;
mating type (–)
Haploid spores (conidia)
Key
Haploid (n)
Dikaryotic (n + n)
Diploid (2n)
Dispersal
Germination
Mating
type (+)
ASEXUAL
REPRODUCTION
Hypha
PLASMOGAMY
Ascus
(dikaryotic)
Conidiophore
Mycelia
Dikaryotic
hyphae
Mycelium
Germination
SEXUAL
REPRODUCTION
KARYOGAMY
Dispersal
Diploid nucleus
(zygote)
Asci
Eight
ascospores
Ascocarp
Figure The life cycle of Neurospora crassa, an ascomycete
Four
haploid
nuclei
MEIOSIS
The life cycle of Neurospora, an ascomycete

13. Basidiomycetes club fungi
Maiden veil fungus
(Dictyphora), a
fungus with an
odor like rotting
meat
Basidiomycetes club fungi
Puffballs emitting
spores
Shelf fungi, important
decomposers of wood
Figure Basidiomycetes (club fungi)

14. Fungus-gardening insects: Leaf-cutting ants depend on fungus to digest plant material to a form the insects can use for their nutrition + +.
Figure Fungus-gardening insects
For the Discovery Video Leafcutter Ants, go to Animation and Video Files.

15. Variety of lichens + + Crustose (encrusting) lichens A foliose
A fruticose (shrublike) lichen
 A foliose
(leaflike)
lichen
Figure Variation in lichen growth forms

16. Anatomy of a common fungal ascomycete lichen
Ascocarp of fungus
Soredia
Fungal
hyphae
Algal
layer
Figure Anatomy of an ascomycete lichen (colorized SEM)
Algal cell
20 µm
Fungal hyphae

17. Fungal Diseases in Plants
Figure Examples of fungal diseases of plants
For the Discovery Video Fungi, go to Animation and Video Files.
(a) Corn smut on corn
(b) Tar spot fungus on
maple leaves
(c) Ergots on rye

18. Staphylococcus Penicillium Zone of inhibited growth
Penicillium: Fungal production of an Antibiotic The mold penicillium produces an antibiotic that inhibits bacteria growth resulting in a clear area between the mold and the bacteria
Staphylococcus
Penicillium
Zone of
inhibited
growth
Figure Fungal production of an antibiotic

19. Review

20. You should now be able to:
List the characteristics that distinguish fungi from other multicellular kingdoms.
Discuss mycorrhizal fungi.
Describe the processes of plasmogamy and karyogamy.
Describe the evidence that multicellularity evolved independently in fungi and animals.

21. Describe the life cycles of Rhizopus stolonifer and Neurospora crassa.
Distinguish among zygomycetes, ascomycetes, and basidiomycetes.
Describe some of the roles of fungi in ecosystems, lichens, animal-fungi mutualistic symbioses, food production, and medicine and as pathogens.