Lecture Objectives

1
Kingdom FungiCh. 27

• Lecture Objectives
• Fungal Characteristics
• Division Zygomycota, Ascomycota, Basidiomycota
• Lichens

2
What makes a fungus a fungus?

• 1. Multicellular
• 2. Cell Walls
• 3. Heterotrophic
• Saprophytic
• Exoenzymes
• 4. Hypha ? Mycelium
• Septate/aseptate
• Haustoria

3
Cell wall
Cell wall
Nuclei
Pore
Septum
Nuclei
(b) Coenocytic hypha
(a) Septate hypha
Fig. 31-3
4

• Aseptate (Coenocytic)
  Septate

5
Reproductive structure
Hyphae
Spore-producing structures
20 µm
Fig. 31-2
Mycelium
6
Haustoria (specialized hypha used to
penetrate host tissue)
Fig 31.4
7
What makes a fungus a fungus cont.

• 5. Reproduction
• Sexual
• Asexual
• BOTH result in spore formation

8
Spores giving rise to hyphae ? mycelium
9
Generalized life cycle
Key
Heterokaryotic stage
Haploid (n)
Heterokaryotic (unfused nuclei from different
parents)
PLASMOGAMY (fusion of cytoplasm)
Diploid (2n)
KARYOGAMY (fusion of nuclei)
Spore-producing structures
Zygote
SEXUAL REPRODUCTION
Spores
ASEXUAL REPRODUCTION
Mycelium
MEIOSIS
GERMINATION
GERMINATION
Fig. 31-5-3
Spores
10
What makes a fungus a fungus cont.

• 6. Metabolism ?Diverse lifestyles
• Decomposers
• Parasites
• Mutualists

11
Beneficial Fungi
12
Fig. 31-26
Staphylococcus
Penicillium
Zone of inhibited growth
13
Parasitic Fungi
14
Fungal Classification

• Domain Eukaraya
• Kingdom Fungi
• Divisions Zygomycota, Ascomycota, Basidiomycota

15
Hyphae
25 µm
Fig. 31-11
Chytrids (1,000 species)
Zygomycetes (1,000 species)
Fungal hypha
Glomeromycetes (160 species)
Ascomycetes (65,000 species)
Basidiomycetes (30,000 species)
16
Phylum Zygomycota (Zygomycetes)

• 1. Fast-growing molds, parasites, and commensal
  symbionts
• 2. Asexual Reproductive Structure Sporangium
• (holder of asexual spores)
• 3. Sexual Reproductive Structure Zygosporangium
• (contains a zygospore (sexual spore))

17
Fig. 31-14
Reproductive structures in Zygomycota
Zygosporanium (sexual)
Sporangia (asexual)
18
Fig. 31-12
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
KARYOGAMY
Sporangia
Spores
Diploid nuclei
Sporangium
ASEXUAL REPRODUCTION
Lifecycle for Phylum Zygomycota, Genus Rhizopus
MEIOSIS
Dispersal and germination
Mycelium
50 µm
19
Phylum Ascomycota (Ascomycetes)

• 1. Marine, freshwater, terrestrial
• 2. Unicellular or multicellular
• 3. Asexual Reproductive Structure Conidiophore
• - asexual spores conidia
• 4. Sexual Reproductive Structure (fruiting body)
  Ascocarp
• - sexual spores ascospores contained in asci
  which line the ascocarp

20
Phylum Ascomycota asexual structures example
here is Penicillium sp.
conidia
conidiophore
21
Phylum Ascomycota Sexual Fruiting Body (ascocarp)
with ascospores
22
Ascocarp Examples
Morchella esculenta, the tasty morel
Tuber melanosporum, a truffle
Fig. 31-15
23
Conidia mating type ()
Key
Haploid spores (conidia)
Haploid (n)
Dikaryotic (n n)
Diploid (2n)
Dispersal
Germination
Mating type ()
ASEXUAL REPRODUCTION
Hypha
PLASMOGAMY
Ascus (dikaryotic)
Conidiophore
Dikaryotic hyphae
Mycelia
Mycelium
SEXUAL REPRODUCTION
Germination
KARYOGAMY
Dispersal
Diploid nucleus (zygote)
Eight ascospores
Asci
Ascocarp
Generalized lifecycle for Phylum Ascomycota
Four haploid nuclei
MEIOSIS
Fig. 31-16
24
Phylum Basidiomycota

• 1. Mushrooms, puffballs, shelf fungi
• 2. ONLY sexual stage observed
• Sexual Reproductive Structure (fruiting body)
  Basidiocarp
• Lined with club-like structures called basidia
• Hold sexual spores called basidiospores

25
Mushroom Examples.
26
Puffballs emitting spores
Fig. 31-17
27
Shelf fungi, important decomposers of wood
28
Maiden veil fungus (Dictyphora), a fungus with
an odor like rotting meat
Fig. 31-17
29
Fig. 31-19-4
Dikaryotic mycelium
PLASMOGAMY
Haploid mycelia
Mating type ()
Mating type ()
Gills lined with basidia
Haploid mycelia
SEXUAL REPRODUCTION
Basidiocarp (nn)
Dispersal and germination
Basidiospores (n)
Basidium with four basidiospores
Basidia (nn)
Basidium
Basidium containing four haploid nuclei
KARYOGAMY
MEIOSIS
Key
Haploid (n)
Dikaryotic (n n)
Diploid nuclei
Diploid (2n)
Basidiospore
1 µm
30
Lichens

• 1. Symbiotic mutualistic association between a
  fungus algae
• Ascomycota Chlorophyta
• 2. Three body types
• Foliose
• Fruticose
• Crustose

31
Figure 31.23
They are the pioneers in rocky substrates, where
there is no soil. Lichens break down the rocky
substrate into soil and their decomposing thallus
fertilize the newly produced soil, making it
possible for the plant habitation.
Lichen in longitudinal section
50 ?m
Fungal hyphae
Algal cell
32
Fig. 31-23
Lichen Body types
 Crustose (encrusting) lichens
A fruticose (shrublike) lichen
 A foliose (leaflike) lichen