1. Domain Eukarya
Kingdom Fungi

2. Anatomy of a fungus
Most fungi grow as multicellular mycelia made up of long, thin filaments called hyphae.
Most of a fungi will be invisible to us. Only the reproductive structures above ground will be seen.

3. Anatomy of a fungus
The hyphae of fungi may or may not be divided into separate cells by septa
Septa No septa

4. Fungi can be multicellular or unicellular
Multicellular mycelia: . This mycelium is from the rind of a piece of Melbury cheese.
The yeast pictured here is baker’s yeast, Saccharomyces cerevisiae.

5. Fungi are absorptively heterotrophic
Pore
Fungi can break down almost any type of organic substance
secrete enzymes to digest food outside
absorb nutrients back in
may be saprobes, detritivores, parasitic, mutualistic, predatory
Cell wall
Septa
Reproductive
structure
Hyphae
Mycelium
Fungal morphology is associated with their mode of nutrition: the fungal mycelium maximizes surface area in relation to volume.

6. Fungal decomposition (saprophytic)

7. Parasitism
Although many fungi infect humans, relatively little human disease is due to fungi.
Parasitic fungi cause major damage to crops such as wheat, corn, and barley.

8. Fungi reproduce by producing spores
The reproductive structures of fungi produce haploid spores
A new fungal mycelium begins with the germination of a haploid spore
spore

9. The Fungal Life Cycle ‘vegetative’ life form typically haploid
May reproduce asexually through haploid spores

10. The Fungal Life Cycle Sexual reproduction through
cytoplasm fusion --> dikaryotic stage (n + n) or heterokaryotic
nuclear fusion--> diploid stage
typically rapid meiosis--> haploid spores

11. Four groups of Fungi

12. Chytridiomycota Mainly aquatic Flagellated spores Basal group of the
Fungi

13. Phylum Zygomycota Rhizopus (bread mold), fruit rot
when two different hyphae join together for sexual reproduction, they form a swollen, thick-walled structure (zygosporangia) that links the hyphae together

14. Figure 31.7 The life cycle of the zygomycete Rhizopus (black bread mold)

15. Figure 31.7x2 Mature zygosporangium

16. Bread mold
Bread Molds, Black Bread Mold, Rhizopus stolonifera, not only grow on Bread, but anywhere there are water and nutrients.

17. Phylum Ascomycota Sac Fungi Fruiting structure called an ascocarp
Produce spores in sac-like compartments called asci
Truffle
Morel

18. Figure 31.10 The life cycle of an ascomycete
Asexual spores produced in conidia
Sexual spores produced in ascocarps

19. Other Ascomycetes Baker’s yeast: Saccharomyces cerevisiae
Penicillin molds
Chestnut blight

20. Phylum Basidiomycota
Club Fungi: Mushrooms, shelf fungi, rusts and smuts, puffballs
Seldom reproduce asexually.

21. Club fungi reproduce sexually by forming spores in a structure called a BASIDIUM (BASIDIA) which can be found lining gills inside the BASIDIOCARP (the mushroom cap).

22. Edible
Mushrooms
Poisonous
Hallucinogenic

23. Table 31.1 Review of Fungal Phyla

24. “Phylum” Glomeromycota?
Mycorrhizae are fungi that associate with plant roots and receive sugars from them.
Two types:
Exomycorrhizae
Endomycorrhizae (also called arbuscular)

25. Ectomycorrhizae grow on the surface of plant roots without penetrating the cells.
EMF
Figure: 29.9a
Caption:
(a) Ectomycorrhizal fungi (EMF) form a dense network around the roots of plants. The combination of root and fungus is called a mycorrhiza. The drawing shows how the interaction works in EMF. Note that their hyphae penetrate the intercellular spaces of the root, but do not enter the cells themselves. 
Common in colder northern climates (decomposition is slow)
The fungus breaks down organic material and delivers nitrogen to the plant.

26. Arbuscular mycorrhizae penetrate the cells of the plant root.
AMF
Root
hair
Figure: 29.9b
Caption:
(b) Interactions of arbuscular mycorrhizal fungi (AMF) with roots. The fungal hyphae penetrate the root cell walls and contact the plasma membrane, where they branch into bushy structures called arbuscules. The photograph shows a fossilized arbuscule, from an AMF, inside a plant cell. The fossil is over 390 million years old.
Common in warmer grasslands & forests (decomposition is rapid).
The fungus delivers phosphorus to the plant.

27. Plant species diversity
Mutualisms:
Increasing the diversity of mycorrhizae in a given habitat increases plant species richness and productivity.
Number of AMF species
Shoot biomass
Plant species diversity 1 2 4 8 14
0.2
0.8
0.4
0.6
130
110 70 90
Effect of AMF species diversity on plants:

28. Mutualisms
Lichens
Lichens are associations of a fungus with either an alga or cyanobacterium.
Lichens are the dominant species in tundra habitats and are important in breaking down rock to form soil.

29. Figure 29.11a Asexual reproduction occurs when “mini-lichens”
are produced.
Asci
produced by
fungus
Fungal layer
Algal layer
Figure: 29.11a
Caption:
(a) In a lichen, green algae or cyanobacteria are enmeshed in a dense network of fungal hyphae. In this example, the fungal participant is an ascomycete.
Fungal layer
Substrate

30. Types of Lichens
crustose, fruticose, foliose

31. Dutch Elm Disease Entered the U.S. in the 1930’s
Has been moving westward ever since
Chicago lost 119,000 trees in 3 years

32. Chestnut blight Entered the U.S. early 20th century
Before: as many as 1 in 4 trees were chestnuts (e. of Mississippi)
100,000s of trees lost (3.5 billion in 40 years?)
Tree now present as an understory tree produced by sprouting from roots

33. Cell walls of fungi are made of chitin
Chitin also makes up the exoskeleton of arthropods
(Cell walls of plants are made of cellulose)

34. Fungi used to be classified with plants
…but there are major differences
Plants
Photosynthetic
Cell wall made of cellulose
Develop from embryos
Fungi
Heterotrophic
Cell wall made of chitin
Develop from spores