FUNGUS-LIKE FUNGUS-LIKE PROTISTSPROTISTSPhylum MyxomycotaPhylum Myxomycota
Phylum AcrasiomycotaPhylum AcrasiomycotaPhylum OomycotaPhylum Oomycota
http://www.nytimes.com/2011/10/04/science/04slime.html?_r=5&pagewanted=all&
CHARACTERISTICS
1. why fungus-like?• appearance• mode of nutrition
2. with centrioles
3. no chitin in cell walls
4. non-photosynthetic
5. 2-stage life cycle• spore-bearing mold-like stage • free-living amoeba-like stage
Stemonitis fusca
http://tywkiwdbi.blogspot.com/2011/11/slime-mold.html, http://www.nationalgeographicstock.com/comp/04/442/1030283.jpg
Comatricha typhoides
Dominant state near rich sources of food
(phagocytic)
Cells aggregate into a slimy mass
when food is scarceand moves to a better location
http://www.nsf.gov/od/lpa/news/03/pr03106_images.htm
Fruiting bodySpore-bearing structure
SLIME MOLDS• Phylum MyxomycotaAcellular slime molds
• Phylum AcrasiomycotaCellular slime molds
Phylum MyxomycotaAcellular or plasmodial slime molds
• plasmodium • large cytoplasmic
mass (multinucleate)• feeding stage
• unfavorable conditions: “fruiting”• sporangia spring up
from plasmodium• meiosis haploid
spores flagellated gametes →diploid zygote (sexual reproduction) →*diploid amoeboid cells
• e.g. Physarumhttp://biodidac.bio.uottawa.ca
http://home.sandiego.edu/~gmorse/2009BIOL221/Study_guide2/plasmodial.jpg
Physarum polycephalum
Comatricha typhoides
Lycolaga epinendrum“wolf’s milk”
Stemonitis splendens“chocolate tube slime”
Arcyris denudata“carnival candy slime”
Brefeldia maxima“tapioca slime”
Tubifera ferruginosa“red raspberry slime”
http://xkcd.com/877/ , http://www.uknature.co.uk/F.septica.jpg, http://i55.tinypic.com/313k32b.jpg, http://i56.tinypic.com/flly6t.jpg
Phylum Acrasiomycotacellular slime molds
• pseudoplasmodium• separated by cell
membranes • cell aggregation
• slug-like form• migrates to form
fruiting body • spores by mitosis
• e.g. Dictyostelium discoideum
Phylum Oomycotawater molds/downy mildew
• cellulosic cell wall• live on organic
matter in water, plant parasites on land
• hyphae finely-branched single-celled filaments
• coenocytic/aseptate no walls between cells
• motile spores
Phytophthora infestans http://www.bluepointenvironmental.com/wp-content/uploads/2012/01/coenocytic-hyphae-60x-LP.jpg
Significance
• decomposers• food source of other organisms
• parasites of plants (grapes, tomatoes, potatoes) and animals
• used to plan routes (shortest distance)
• rich areas for biological study
http://www.gardencentre.ie/blog/wp-content/uploads/2012/05/potato-blight.jpg, http://media.treehugger.com/assets/images/2011/10/tokyo-mold-railway.jpg