1. What is the biggest organism in this Oregonian forest?

2. Hint, it is pictured

3. The honey mushroom fungus

4. Fun-gi vids pig decomposition time-lapse fungus time-lapse
growing mold time-lapse
parasitic fungi time-lapse

5. Chapter 31
Fungi

6. Concept 31.1: Fungi are heterotrophs that feed by absorption
Fungi are heterotrophs and absorb nutrients from outside of their body
Fungi use enzymes to break down a large variety of complex molecules into smaller organic compounds
Fungi exhibit diverse lifestyles
Decomposers
rabbit decomposing
Parasites
previously shown, with new bonus mushroom and slime mold time-lapse
Mutualists
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7. Animation: Fungal Reproduction and Nutrition Right-click slide / select “Play”
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8. A mycelium’s structure maximizes its surface area-to-volume ratio
Anatomy basics
Fungi consist of mycelia, networks of branched hyphae adapted for absorption
A mycelium’s structure maximizes its surface area-to-volume ratio
Fungal cell walls contain chitin
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9. Reproductive structure
Figure 31.2
Reproductive structure
Hyphae
Spore-producing structures
Figure 31.2 Structure of a multicellular fungus.
60 m
Mycelium

10. TWO FORMS OF HYPHAE Cell wall Nuclei Cell wall Pore Septum Nuclei
(a) Septate hypha
(b) Coenocytic hypha
Figure 31.3 Two forms of hyphae.

11. 1 pinch of soil can contain 1 km of hyphae

12. How much hyphae did she eat?

13. Some unique fungi have specialized hyphae called haustoria that allow them to penetrate the tissues of their host
Hyphae
Nematode
25 m
(a) Hyphae adapted for trapping and killing prey
Fungal hypha
Plant cell wall
Figure 31.4 Specialized hyphae.
Plant cell
Plant cell plasma membrane
Haustorium
(b) Haustoria

14. Mycorrhizae are mutually beneficial relationships between fungi and plant roots, which most vascular plants have
Ectomycorrhizal fungi form sheaths of hyphae over a root and also grow into the extracellular spaces of the root cortex
Arbuscular mycorrhizal fungi extend hyphae through the cell walls of root cells and into tubes formed by invagination of the root cell membrane
Which is pictured  ?
Which is pictured on the previous slide?
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15. Concept 31.2: Fungi produce spores through sexual or asexual life cycles
Fungi propagate themselves by producing vast numbers of spores, either sexually or asexually, or both
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16. Fungi life cycle paths can be funky
Key
Haploid (n)
Heterokaryotic
Diploid (2n)
Spore-producing structures
Spores
ASEXUAL REPRODUCTION
Mycelium
Figure 31.5 Generalized life cycle of fungi.
GERMINATION

17. Spore-producing structures
Fungi life cycle paths can be funky
Key
Haploid (n)
Heterokaryotic stage
PLASMOGAMY
Heterokaryotic
Diploid (2n)
Spore-producing structures
KARYOGAMY
SEXUAL REPRODUCTION
Spores
ASEXUAL REPRODUCTION
Mycelium
Zygote
Figure 31.5 Generalized life cycle of fungi.
GERMINATION

18. Spore-producing structures
Fungi life cycle paths can be funky
Key
Haploid (n)
Heterokaryotic stage
PLASMOGAMY,
based on pheromone compatibility
Heterokaryotic
Diploid (2n)
Spore-producing structures
KARYOGAMY
SEXUAL REPRODUCTION
Spores
ASEXUAL REPRODUCTION
Mycelium
Zygote
Figure 31.5 Generalized life cycle of fungi.
GERMINATION
MEIOSIS
GERMINATION
Spores

19. © 2011 Pearson Education, Inc.

20. Asexual Reproduction
In addition to sexual reproduction, many fungi can reproduce asexually
Molds produce haploid spores by mitosis and form visible mycelia
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21. Figure 31.7
CHECK-IN Q
Yeast are unicellular and reproduce by budding. Then what makes them fungi?
10 m
Parent cell
Figure 31.7 The yeast Saccharomyces cerevisiae in several stages of budding (SEM).
Bud

22. Concept 31.3: The ancestor of fungi was an aquatic, single-celled, flagellated protist
DNA evidence suggests that
Fungi are most closely related to unicellular nucleariids
Animals are most closely related to unicellular choanoflagellates
Based on this, did fungi and animals split before or after the emergence of multicellularity?
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23. The Move to Land
If fungi are heterotrophic, how does it make sense that they were among the first land colonizers?
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24. The Move to Land
If fungi are eukaryotic, how does it make sense that they were among the first land colonizers?
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25. Concept 31.4: Fungi have radiated into a diverse set of lineages
Molecular analyses have helped clarify evolutionary relationships among fungal groups, although areas of uncertainty remain
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26. Figure 31.11 Exploring: Fungal Diversity
Hyphae
25 m
Chytrids (1,000 species)
Zygomycetes (1,000 species)
Fungal hypha
25 m
Glomeromycetes (160 species)
Ascomycetes (65,000 species)
Figure Exploring: Fungal Diversity
Basidiomycetes (30,000 species)

27. Chytrids
Chytrids (phylum Chytridiomycota) are found in freshwater and terrestrial habitats
They can be decomposers, parasites, or mutualists
Molecular evidence supports the hypothesis that chytrids diverged early in fungal evolution
Chytrids are unique among fungi in having flagellated spores, called zoospores
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28. Video: Allomyces Zoospore Release
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29. Video: Phlyctochytrium Zoospore Release
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30. Zygomycetes
The zygomycetes (phylum Zygomycota) exhibit great diversity of life histories
They include fast-growing molds, parasites, and commensal symbionts
The life cycle of black bread mold (Rhizopus stolonifer) is fairly typical of the phylum
Its hyphae are coenocytic
Asexual sporangia produce haploid spores
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31. Chytrids Zygomycetes Glomeromycetes Ascomycetes Basidiomycetes
Figure 31.UN02
Chytrids
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Figure 31.UN02

32. Flagellum Figure 31.13 PLASMOGAMY Mating type ()
Gametangia with haploid nuclei
Mating type ()
Rhizopus growing on bread
100 m
Young zygosporangium (heterokaryotic)
SEXUAL REPRODUCTION
Dispersal and germination
Zygosporangium
Flagellum
KARYOGAMY
Sporangia
Figure The life cycle of the zygomycete Rhizopus stolonifer (black bread mold).
Diploid nuclei
Sporangium
ASEXUAL REPRODUCTION
MEIOSIS
Key
Dispersal and germination
Haploid (n)
Heterokaryotic (n  n)
Mycelium
50 m
Diploid (2n)

33. The zygomycetes are named for their sexually produced zygosporangia
Zygosporangia are the site of karyogamy and then meiosis
Zygosporangia, which are resistant to freezing and drying, can survive unfavorable conditions
Some zygomycetes, such as Pilobolus, can actually “aim” their sporangia toward conditions associated with good food sources
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34. Figure 31.14
Figure Pilobolus aiming its sporangia.
0.5 mm
Pilobolus aiming its sporangia toward light as that is where edible vegitation would be growing (grass). Grass is eaten, spores spread in feces.

35. Glomeromycetes
The glomeromycetes (phylum Glomeromycota) were once considered zygomycetes
They are now classified in a separate clade
Glomeromycetes form arbuscular mycorrhizae
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36. Chytrids Zygomycetes Glomeromycetes Ascomycetes Basidiomycetes
Figure 31.UN03
Chytrids
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Figure 31.UN03

37. Figure 31.15
Figure Arbuscular mycorrhizae.
2.5 m

38. Ascomycetes
Ascomycetes (phylum Ascomycota) live in marine, freshwater, and terrestrial habitats
Ascomycetes produce sexual spores in saclike asci contained in fruiting bodies called ascocarps
Ascomycetes are commonly called sac fungi
Ascomycetes vary in size and complexity from unicellular yeasts to elaborate cup fungi and morels
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39. Chytrids Zygomycetes Glomeromycetes Ascomycetes Basidiomycetes
Figure 31.UN04
Chytrids
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Figure 31.UN04

40. Morchella esculenta, the tasty morel
Figure 31.16
Morchella esculenta, the tasty morel
Tuber melanosporum, a truffle
Figure Ascomycetes (sac fungi).

41. Ascomycetes include plant pathogens, decomposers, and symbionts
Ascomycetes reproduce asexually by enormous numbers of asexual spores called conidia
Conidia are not formed inside sporangia; they are produced asexually at the tips of specialized hyphae called conidiophores
Neurospora crassa, a bread mold, is a model organism with a well-studied genome
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42. Figure 31.17 The life cycle of Neurospora crassa, an ascomycete.
Conidia; mating type ()
Key
Dispersal
Haploid (n)
Germination
Mating type ()
Dikaryotic (n  n)
ASEXUAL REPRODUCTION
Diploid (2n)
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

43. Basidiomycetes
Basidomycetes (phylum Basidiomycota) include mushrooms, puffballs, and shelf fungi, mycorrhizae, and plant parasites
The phylum is defined by a clublike structure called a basidium, a transient diploid stage in the life cycle
The basidiomycetes are also called club fungi
Many basidiomycetes are decomposers of wood
© 2011 Pearson Education, Inc.

44. Chytrids Zygomycetes Glomeromycetes Ascomycetes Basidiomycetes
Figure 31.UN05
Chytrids
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Figure 31.UN05

45. Puffballs emitting spores
Figure 31.18
Shelf fungi
Puffballs emitting spores
Figure Basidiomycetes (club fungi).
Maiden veil fungus (Dictyphora)

46. Mushrooms are examples of basidiocarps
The life cycle of a basidiomycete usually includes a long-lived dikaryotic mycelium
In response to environmental stimuli, the mycelium reproduces sexually by producing elaborate fruiting bodies called basidiocarps
Mushrooms are examples of basidiocarps
The numerous basidia in a basidiocarp are sources of sexual spores called basidiospores
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47. Figure 31.19 The life cycle of a mushroom-forming basidiomycete.
Dikaryotic mycelium
Key
PLASMOGAMY
Haploid (n)
Dikaryotic (n  n)
Mating type ()
Diploid (2n)
Mating type ()
Haploid mycelia
Gills lined with basidia
SEXUAL REPRODUCTION
Basidiocarp (n  n)
Dispersal and
germination
Basidiospores (n)
Basidium with four basidiospores
Basidia (n  n)
Basidium
Figure The life cycle of a mushroom-forming basidiomycete.
Basidium containing four haploid nuclei
KARYOGAMY
MEIOSIS
Diploid nuclei
1 m
Basidiospore

48. Basidiomycetes can produce mushrooms quickly
Figure 31.20
Figure A fairy ring.
Basidiomycetes can produce mushrooms quickly
Some species may produce “fairy rings”

49. Imagine a fungi-free world…

50. Concept 31.5: Fungi play key roles in nutrient cycling, ecological interactions, and human welfare
Fungi interact with other organisms as decomposers, mutualists, and pathogens
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51. Fungi as Decomposers/Nutrient recylers
Fungi are efficient decomposers of organic material including cellulose and lignin
Fungi are also used in bioremediation projects
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52. Fungi as Mutualists
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53. Fungus-Plant Mutualisms
Mycorrhizae are enormously important in natural ecosystems and agriculture
Plants harbor harmless symbiotic endophytes, fungi that live inside leaves or other plant parts
Endophytes make toxins that deter herbivores and defend against pathogens
Most endophytes are ascomycetes
© 2011 Pearson Education, Inc.

54. Endophyte not present; pathogen present (EP)
Figure 31.21
RESULTS
Endophyte not present; pathogen present (EP)
Both endophyte and pathogen present (EP) 30 15 20 10
Leaf mortality (%)
Leaf area damaged (%)
Figure Inquiry: Do endophytes benefit a woody plant? 10 5
EP
EP
EP
EP

55. Fungi-animal symbiosis
Figure Fungus-gardening insects.

57. Lichens
A lichen is a symbiotic association between a photosynthetic microorganism and a fungus
The photosynthetic component is green algae or cyanobacteria
The fungal component is most often an ascomycete
The symbioses are so complete that lichens are given scientific names
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58. A foliose (leaflike) lichen
Figure 31.23
A foliose (leaflike) lichen
Crustose (encrusting) lichens
Figure Variation in lichen growth forms.
A fruticose (shrublike) lichen

59. Ascocarp of fungus Soredia Fungal hyphae Algal layer 50 m
Lichen anatomy
Ascocarp of fungus
Soredia
Fungal hyphae
Algal layer
50 m
Figure Anatomy of an ascomycete lichen (colorized SEM).
Fungal hyphae
Algal cell

60. Lichens are important pioneers on new rock and soil surfaces
Lichens may have helped the colonization of land by plants 550–600 million years ago
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61. Fungi as Pathogens
About 30% of known fungal species are parasites or pathogens, mostly on or in plants
Each year, 10% to 50% of the world’s fruit harvest is lost due to fungi
Some fungi that attack food crops are toxic to humans
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62. Tar spot fungus on maple leaves
Figure 31.25
(b)
Tar spot fungus on maple leaves
Figure Examples of fungal diseases of plants.
(a) Corn smut on corn
(c) Ergots on rye

63. Fungi caused Salem Witch Trials?
Ergotism is characterized by gangrene, nervous spasms, burning sensations, hallucinations, and temporary insanity
Ergots contain lysergic acid, the raw material for LSD
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64. Global amphibian populations are down due to fungal infection (mycosis)
California
Sixty Lake Basin
2004
Yellow-legged frogs killed by B. dendrobatidis infection N
2005
Figure Impact: Amphibians Under Attack
Key
Boundary of chytrid spread
2006
Lake status in 2009:
2007
2008
Frog population extinct
Treatment lake: frogs treated with fungicides and released

65. Practical Uses of Fungi
Humans eat many fungi and use others to make cheeses, alcoholic beverages, and bread
Some fungi are used to produce antibiotics for the treatment of bacterial infections
For example, the ascomycete Penicillium
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66. Fungal production of antibiotic
Staphylococcus
Penicillium
Zone of inhibited growth
Figure Fungal production of an antibiotic.

67. Distinguishing Features of Morphology and Life Cycles
Figure 31.UN06
Fungal Phylum
Distinguishing Features of Morphology and Life Cycles
Chytridiomycota (chytrids)
Flagellated spores
Zygomycota (zygote fungi)
Resistant zygosporangium as sexual stage
Glomeromycota (arbuscular mycorrhizal fungi)
Arbuscular mycorrhizae formed with plants
Ascomycota (ascomycetes, or sac fungi)
Sexual spores (ascospores) borne internally in sacs called asci; vast numbers of asexual spores (conidia) produced
Figure 31.UN06
Basidiomycota (basidiomycetes, or club fungi)
Elaborate fruiting body (basidiocarp) containing many basidia that produce sexual spores (basidiospores)

68. Figure 31.UN08
Figure 31.UN08

69. Figure 31.UN09
Figure 31.UN09

70. Figure 31.UN10
Figure 31.UN10