Post on 14-Dec-2015
What is a fungus?
A eukaryotic, multicellular, heterotrophic organism that does not have chlorophyll.
Mycology = study of fungi
Structure:
The main body of most fungi is made up of fine, branching, usually colourless threads called hyphae.
Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.
Structure:
Fruiting bodies (such as mushrooms) are made up of thick collections of hyphae.
Fruiting bodies can produces spores
Ecological Importance:
Decomposers: recycle nutrients (often called saprobes or saprophytes)
Parasites: feed on living organisms
Symbiosis: mutualistic relationships
Ex. lichens and mycorrhizae
How fungi feed:
Extracellular digestion: As the hyphae grow across a food surface, they
release digestive chemicals These chemical break large organic molecules into
smaller molecules The smaller molecules diffuse into the fungi
How Fungi Reproduce:
Most fungi can reproduce with asexual or sexual reproduction
Fragmentation: (asexual) when a piece of hyphae brakes off, a new piece can grow back
Spores: windblown reproductive cells that help fungi disperse to new locations
Spore can be asexual or sexual
Diversity of Fungi:
Over 100,000 species of fungi 4 phyla
Classified according to their reproductive structures
1. Phylum Zygomycota:
Example: bread molds Spores for reproduction
Sporangia (a spore case) Hyphae grow into the food source
2. Phylum Ascomycota:
Sac fungi Produce a sac-like
reproductive structure called an ascus
Examples: Morels and truffles
(for eating) Yeast (only
unicellular fungi) Athlete's foot,
ringworm Plant diseases: Dutch
elm and ergot
3. Phylum Basidiomycota:
Club Fungi Examples includes mushrooms, shelf fungi and puffballs Produce spore in a club shaped structure called basidia The basidia are located under the cap in the gills
Amanita muscaria extremely poisonous!
http://www.mykoweb.com/photos/large/Amanita_muscaria(mgw-03).jpg
4. Deuteromycota (Imperfect Fungi)
Reproduces asexual only Many are used in food production, such as
cheeses and soy sauce Examples are Penicillium and Aspergillis
Developed penicillin the antibiotic from this
Causes lung disease in humans
Lichens
Mutualistic relationship (both benefit from Mutualistic relationship (both benefit from living together) between a fungi and a living together) between a fungi and a cyanobacteria or algaecyanobacteria or algae Fungi provides shelter and moisture and
photosynthetic partner provides the food
Importance: food source for Arctic animals(caribou,etc) pioneer organisms in primary succession indicator for air pollution
Pseudocyphellaria aurata, "green specklebelly", on the bark of a plane tree in the mountains of Tennessee. In Madagascar, a tea made from this lichen is used to treat indigestion.
http://www.lichen.com/bigpix/Paurata.html
Cetrelia chicitae ("sea-storm lichen") on mossy rock, north shore of Lake Superior, Ontario.
http://www.lichen.com/bigpix/Cchicitae.html