1. Chapter 14
Fungi
Heterotrophic organisms once considered to be primitive or degenerate plants lacking chlorophyll

2. Ecological decomposers
Importance of Fungi
Together with Heterotrophic bacteria
Ecological decomposers

3. Decomposing fruit- Rhizopus

4. Root-rot fungus- white mycelial causes disease in living trees
Acts as decomposers on dead plants

5. Root rot
Ouch!!!

6. Fungi
Composed of Hyphae
Heterotrophic absorbers

7. Characteristics of Fungi
Composed of Hyphae
Fungal filaments= “Cobwebby” strands of subterranean “white stuff”
Mycelium

9. Fungi form important symbiotic relationships
80% of all vascular plants species from mutually beneficial associations called mycorrhizae between roots and fungi
Plant nutrition
Lichens form symbiotic relationship with fungi, algal, or cyanobacterial cells

10. Fungi and insects
Endophytes- fungi live in plants produce toxic that protect host

11. Four phyla of fungi Zygomycota Ascomycota next week lecture
Chytridiomycota
Zygomycota
Ascomycota next week lecture
Basidiomycota next week lecture

12. Chars of Fungi All have cell wall
Cell wall composed of polysaccharide- chitin
Chitin more resistant to microbial degradation than cellulose

13. All Fungi Heterotrophic Absorbers
Unable to engulf small microorganisms
Secrete enzymes and absorb smaller molecules
Absorb food mostly at or near the growing tips of their hyphae

14. Fungi obtain their food
Either as Saprophytes or
As mutualistic symbionts

15. Some
Obtain energy through fermenation producing ethyl alcohol from glucose (i.e. yeast)

16. Fungi Store energy
Polysaccharide
Glycogen
Lipids

17. Fungi reproduce both sexually and asexually
Reproduce through the formation of spores that are produced sexually or asexually
Most are nonmotile spores
Some are dry and small and airborne
Some are slimy and stick to the bodies of insects and other arthropods
Some propel into air- phototropism

18. Common method of asexual reproduction in fungi
By means of spores
Either produced in sporangia
The sporangium is a saclike structure, the entire contents of which are converted into one or more spores

19. Asexual reproduction Or Hyphal cells called conidiogenous cells
Spores produced by conidiogenous cells occur singly or in chains called conidia

20. Asexual repro
Some Reproduce by fragmentation of their hyphae

22. Sexual reproduction Three distinct phases
First two are phases of fertilization (syngamy)
Plasmogamy- the fusion of protoplasts
Karyogamy- the fusion of nuclei (some don’t fuse forming a dikaryon)

23. Give rise to gametes by
differentiation
Divide by mitosis
gametangia 4
Spores

24. The last phase is meiosis
Sexual reproduction results in the formation of specialized spores such as zygospores, ascospores, basidiospores.

25. Zygospores Zygospores
Asexual and sexual reproduction (by means of haploid spores)
Sexually producing zygospores require two compatible species

26. Zygomycetes: Phylum Zygomycota
Live on decaying plant and animal matter in soil
Some are parasites of plants, insects or small soil animals
Others form symbiotic relationships- endomycorrhizea- with plants occasionally cause infection in animals
Rhizopus stolonifer- best known zygomycetes

27. Life cycle of Rhizopus stolonifer

28. Gametangia the gamete producing structures are in the
Process of producing a zygospore

29. Zygospore develops within the thick walled zygosporangium