Ch 19 Fungi Flashcards
what are common forms of fungi
common forms include molds, mildew, and mushrooms
are fungi eukaryotes or prokaryotes
eukaryotes
are fungi autotrophs or heterotrophs
heterotrophs
how do most fungi acquire food
- lots of saprophytes
- some parasites and symbiotes
- Absorb food through the cell wall and membrane
- enzymes inside breakdown food
what roles do fungi play in the environment
fungi are major parts of decomposers and along with bacteria help recycle dead organims
what is up with yeast
yeast are single cellular fungi, and are an exception to many fungal phenotypes
what is the general structure of fungi
- fungi are made of many little filaments tangled together into a form called a mycelium
- individual filaments are called hyphae
- cell walls can be made of chitin or cellulose
how do fungi asexually reproduce
- asexual reproduction is due to spores or by hyphae fragmentation
- spores are sometimes formed in sporangia
- specialized hyphae called sporangiophores hold spores
what types of reproduction do fungi do
asexual and sexual
how do fungi have sex
- in many fungi two mating types exist, + and -
- when hyphae of opposite mating types meet they form a gametangium or gamete forming structure
- the gametangium fuse and some of the nucleic acid pair and form zygote nuclei
- most of the time fungi have haploid nuclei (N)
- Diploid nuclei form during sexual reproduction they then meioses into haploids that dominate the remainder of the life style
how are fungi classified
- Fungi are classified according to reproductive methods and general structure into 5 phyla:
- Oomycota
- Zygomycota
- Ascomycota
- Basidiomycota
- Deuteromycota
what are oomycota
Oomycota: Protist like fungi
- closely related to plant like protists
- oomycota from white fuzz on aquarium fish or organic material in water
- known as water mold though they can live on land
- cellulose cell walls
- produce motile sperm
- hyphae lack cross walls and are multinucleic
- have two specialized structures for reproduction
- the antheridium produces sperm
- oogonium produces eggs and is where fertilization occurs
what are zygomycota
Zygomycota: common molds
- terrestrial
- thick walled zygotes, zygospores
- mostly lace cross walls
- from molds, rhizoid hyphae penetrate the inside where stolons hyphae grow on the outside
- sporangiophores push into the air and release spores
what are asomycota
Ascomycota: Sac Fungi
- largest phyla of fungi
- have cross walls and individual cells
- can b visible (like morel) or invisible (like yeast)
- asexual spores called conidia form hypha called conidiophores
- a sac, called the asous is formed after sexual reproduction
- acospores are sexually produced spores
- some have fruiting bodies
what are Basidiomycota
Basidiomycota: club fungi
- most mushrooms
- have a structure called basidium that produces spores (found in mushroom caps)
- basidiospore germinate into primary haploid mycelia, these create secondary mycelia with nuclei from opposite mating types, eventually the mycelia form mushrooms (fruiting bodies) very fast form cytoplasm and mycelia
- gills in mushrooms are lined with basidia and the 2 nuclei for zygotes at this point
what are deuteromycota
Deuteromycota: imperfect fungi
- no know sexual reproduction
- can be similar to other phyla
- reproduce asexually with conidia
what is the ecological importance of fungi
- decompose and recycle living matter
- most species use in some way the nutrients recycled by fungi
where are fungi found
- pretty much every where
- spores nearly every place
- large mycelia span vaste areas
how are fungal spores dispersed
produce many spores that are dispersed by the wind or animals, etc
what are the symbiotic relationships of fungi
- some harmful
- some beneficial
- lichens are a partner ship of fungi ( a ascomycota or basidiomycota) and a photosynthetic organisms (cyanobacteria or algae), the photosynthesized gives energy and the fungi finds water and minerals
- mycorrhizae form between plants and fungi and the plant gives energy and the fungi mycelia acts are rocks
how do humans interact with fungi
- yeasts like the genus sacchoromyces make bread, wine, etc. the yeast have no 02, ferments produce 02 and alcohol
- yeast can be used in cloning to produce protein products of genes
- we eats mushrooms (some) while other are poisons
what are some diseases caused by fungi
- potato blight
- 1945 ireland
- phytophthora infestans
- reduce potatoes to sacs of spores
- 1,000,000 people died
- wheat rust
- 1900s
- killed wheat plants
- added to Great Depression in 1930s
- ruin whole wheat crops
- other plant diseases
- can smut
- mildews
- loss of 15% of crops in temperate climates
- and 50% in tropics
- human diseases
- athletes foot = deuteromycotes species
- ring worms
- yeast infections = candida Albans
- animals diseases
- cordyceps lloydii is ant zombie
