Fungi are eukaryotic organisms that are nonphotosynthetic and include mushrooms, molds, yeasts, and lichens. They have cell walls made of chitin and are more genetically similar to animals. Fungi play important roles as decomposers that recycle nutrients and are used for food, antibiotics like penicillin, and symbiotic relationships with plants. They reproduce both sexually through structures like ascocarps and basidiocarps and asexually via spores. Major fungal groups include chytridiomycota, zygomycota, ascomycota, and basidiomycota which differ in their reproductive structures and life cycles.

1. Lecture on Fungi
11/25/13 Monday

2. Characteristics
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nonphotosynthetic
Most are saprobes (feed on dead things)
Cell wall made of chitin
Genetically more similar to animals

3. Importance
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Decomposer and recycler of nutrients
Consumed as food and food production
Truffles, morels, mushroom
Antibiotic: penicillin

4. Antibiotics
• Cyclosporin prevent organ rejection
• Statin lowers cholesterol
• Penicillin

5. Mutual symbionts of pants
• Mycorrhizae
• lichens

6. lichen
• Mutual symbiont of algae
• Indicator of air pollution
• Source of dyes (litmus)

7. Three forms of lichen (Know for lab
exam)
1. Crustose: crustlike, growing tight against the
substrate.
2. Foliose: leaflike, with flat sheets of tissue not
tightly bound
3. Fruticose: free-standing branching tubes.

8. Mycoses
• Agents of
disease

9. Four Fungal diseases
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Thrush: yeast infection
Histoplasmosis : lung infection
Aspergillosis : mold in your house
Cryptococcus /Valley fever: can lead to
pneumonia and meningitis

10. ergotism
• Clavicles fungus
• Salem witch trials

11. Sporotrichosis: rose gardener’s disease
• Fungal antibiotics are harmful; humans and
fungi are eukaryotes. Bacterial infections are
better to treat because they are prokaryotes

12. Tinea Infections (Ringworm)
• Infection on skin and nail’s keratin

13. Claviceps purpurea, cause of
ergotism

14. Plant diseases caused by fungi
1. Rust
2. Apple Scab
3. smut

15. cellular
• Unicellular (yeast)
• Multicellular (mold)
• Some are yeast inside and mold outside the
body

16. Structure
• Mycelia: networks of branched hyphae (cells)
• Septum (cell wall) separating the hyphae
• Coenocyte fungi lack septa and cellular
contents can flow between the hyphae

17. Septate hyphae
• Septum: a cross-wall
formed in association
with the mitotic division
of a cell, laid down
between the cells,
usually at regular
intervals.

18. Coenocytic hyphae
• multinucleate mass of
protoplasm resulting
from repeated nuclear
division unaccompanied
by cell fission

19. Types of mycorrhizae fungi
• Ecto : grow into the extracellular species of
the root cortex (truffle)
• Endo: grow into the root cell (orchid)

20. Reproduction
• Plasmogamy: union of two parent mycelia
• Heterokaryon: cell or mycelium in some fungi
that do not result in the fusion of two nuclei
• Dikaryotic: the nucleus pair off two to a cell

21. Karyogamy (nuclear fusion)
• Produce diploid cells
• Takes a long time
• 2n phase is short-lived and undergo meiosis,
producing 1n spores

22. sporangium
• Fungal structures where asexual spores are
produced
• exam

23. budding
• Simple cell division in which yeast repouce
asexually

24. Imperfect fungi/deuteromycetes
• Some fungi have no known sexual stage

25. Evolution
• Fungi descended from protists
• Fungi and Animalia are sister kingdoms

26. Groups you must know
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2.
3.
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Chytridiomycota: earliest fungi
Zygomycota
Glomeromycota
Ascomycota
Basidiomycota

27. Chytridiomycota: earliest fungi
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Found in water
Saprobic or parasitic
B. dendrobatids: decline of frog population
Chytrids diverged earliest

28. Zoospores: flagellated spores
• Only chytrids have zoospores

29. Zygomycota
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Asexual and sexual spores
Zagospore (sexual)
Sponragiospores (asexual spores)
Very cold/heat tolerant, responsible for food
spoilage
• Black bread mold Rhizopustoloniser
• pilobolus

30. Life cycle
• Zygomycota

31. glomeromycota
• Arbuscular mycorrhizae: endo
• 80% of all vascular plants have arbuscular
mycorrhize
• Reproduce asexually
• Help plants absorb phosphorous and help a
crucial role in colonization of land by plants

32. Ascomycetes (cup fungi)
• Asci: sexual spores that are found in saclike
structure
• Reproduce sexually
• Many asci are found on the fruiting body
called ascocarp
• Ex. Truffle
• Conodia: asexual spores
• Conodiophore: structure

33. Penicillium conidiophores

34. Sporangium conidiophore

35. Aspergillus condiophore

36. Ascomycetes
• Truffles, yeast,
penicillin, morels

37. Ascomycetes
• Fungal partner in lichen
is an ascomycete

38. Basidiomycetes: typical mushroom
• Basidium: structure
where sexual spores
(basidiospores) are
produced
• Gills with basidia

39. Reproduction of
Basidiomycetes: typical
mushroom
• Sexual mostly resulting in
dikaryotic fruiting bodies
called basidiocarps
(mushroom)
• Karygomy occurs in the gills
of the mushroom cap where
basidium and basidiophores
are found
• Asexual reproduction is rare
and occur via fragmentation
• Ex. Club fungi, rust, smut,
puff balls, shelf fungi,
mushrooms

40. Basidiomycete life cycle
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Basidiomycetes – Fungi
Key Points
The basidiomycetes (phylum Basidiomycota) are comprised of roughly
30,000 species that include mushrooms, shelf fungi and puffballs.
The basidium is a specific, club-shaped cell where karyogmay is carried out
followed by meiosis. This gives rise to the name club fungus.
A diploid nucleus is formed during karyogamy and then undergoes meiosis,
resulting in four haploid nuclei. The basidium divides into four arms, with a
single haploid nucleus in each that will develop into a basidiospore.
The reproductive cycle of basidiomycetes has a long dikaryotic mycelium
stage allowing for genetic diversity as a result of recombination.
Basidiomycetes are particularly important in nature as decomposers of
plant material, especially dead wood and trees.
Terms
basidium
a small structure, shaped like a club, found in the Basidiomycota phylum of
fungi, that bears four spores at the tips of small projections
Karyogamy
The fusion of two nuclei within a cell.
Mycelium
The vegetative part of any fungus, consisting of a mass of branching,
threadlike hyphae, often underground.
mycelium
the vegetative part of any fungus, consisting of a mass of branching,
threadlike hyphae, often underground

41. Glossary
• http://bugs.bio.usyd.edu.au/learning/resourc
es/Mycology/Glossary/glossary_a_b.shtml