chapter 23 - fungi diversity Flashcards
(39 cards)
1
Q
Who cares about fungi?
A
- economic: yeasts, food, crop disease, human maladies, fermentation
- ecological: interaction w other organisms, decomposition, and succession
2
Q
Fungi characteristics
A
- eukaryotes
- heterotrophic: absorb nutrients
- cells walls generally contain chitin fibers
- storage carb: often glycogen
3
Q
Which fungi features are more animal like?
A
- eukaryotes
- heterotrophs (consumers)
- store carb: glycogen
4
Q
Which fungi features are more plant like?
A
- cell walls with chitin fibers
- eukaryotes
5
Q
Fungi structures
A
- single cells or filaments are called hyphae; ex: yeasts
- mycelium: a bunch of hyphae
- hyphae can be septate or nonseptate
6
Q
Nonseptate hyphae
A
- individual cells with NO physical call wall boundary
- cells are singular with one nuclei
7
Q
Septate hyphae
A
- distinctive cell wall between cells
- each cell with a nuclei
8
Q
Fungi reproduction
A
- asexually or sexually through spores
- plasmogamy (sexual)
- karyogamy (sexual)
- asexual spore production
9
Q
What is plasmogamy?
A
- a type of fungi sexual reproduction
- involves fusion of the cytoplasm
10
Q
What is karyogamy?
A
- a type of fungi sexual reproduction
- involves the fusion of two haploid nuclei
11
Q
what is produced if karyogamy does not occur immediately?
A
- follows plasmogamy and leads to the development of a dikaryon
- two genetically different nuclei in one cell
12
Q
What is a dikaryon?
A
- intermediate between plasmogamy and karyogamy
- contains two genetically DIFFERENT nuclei.
- occurs after fusion of cytoplasm
13
Q
Fungi asexual reproduction
A
- asexual spore produced within sporangium or as a conidia w/o enclosure
14
Q
What are some fungal like protists?
A
- slime molds and water molds
- skim
15
Q
Chitridiomycota
A
- part of the fungi kingdom
- typically, parasites of plants, animals, and other fungi
- associated with world-wide amphibian decline
- infects the dermal cells of amphibians and reduces respiration
16
Q
Zygomycota
A
- part of the fungi kingdom
- named for thick-walled spore-containing zygosporangia
- mostly nonseptate hyphae
17
Q
Zygomycota reproduction
A
- sexual or asexual
- much is asexual
- if sexual, a diploid portion is formed that can release spores
18
Q
AM fungi
A
- arbuscular mycorrhizae
- plant/fungi metabolism
- obligate mutualists w/ plants, unable to grow w/o plants
- form endomycorrhizal associations
19
Q
Ascomycota
A
- asci: sac, “sack-fungi”
- septate dikaryon make up the ascocarp
- ascocarp: sporulating body
- karyogamy: fusion of nuclei
- karyogamy, meiosis, then mitosis leads to 8 ascospores/asci
20
Q
examples of Ascomycota
A
- brewers/baker’s yeast
- morels
- truffles
- female infectious yest
- athletes foot fungi
21
Q
Ascomycota reproduction
A
- nuclei do NOT fuse together but cytoplasm does (plasmogamy)
- two haploid nuclei in each cell
- organism develops after fusing of nuclei (karyogamy)
- then meiosis then mitosis
- how morel mushrooms grow
- each cycle 8 ascospores are formed
22
Q
How many ascospores are formed in Ascomycota reproduction?
A
- eight
23
Q
Truffles
A
- type of Ascomycota
- grow underground
- dogs with better scent are trained to find them
- expensive
24
Q
Ascomycota ‘imperfect fungi’
A
- Ascomycota includes the imperfect fungi
- no known sexual stages
- DNA links to ascomycota
25
Examples of imperfect fungi
- penicillium: source of antibiotic penicillin, component of Roquefort cheese
- Aspergillus: can cause aspergillosis, lung infection, compost heap is a likely source
- Geomyces destructants: causing white nose syndrome in insect eating bats
26
Who is more susceptible to Aspergillus induced lung infections?
- cystic fibrosis patients
- asthma patients
27
What is white nose syndrome?
- Geomyces destructants induced syndrome of insect eating bats
- fungi gets in the brain and confuses bats
- bats get confused and hunt for insect during winter but there aren't any
- waste their energy
- no food + waste energy = die
28
Basidiomycota
- spores produced on basidium: tiny pegs or clubs called club fungi
- dikaryon, septate hyphae make sporulating body (basidiocarp)
- karyogamy and meiosis occur in the basidium to produce basidipores
- most mushrooms, puffballs, rusts, and smuts
29
Where are spores stored in Basidiomycota?
- basidiocarp on the gills or holes in shell fungi
- spores released by the wind
30
Ecological roles of Basidiomycota?
- parasitic (harm host) or mutualistic symbiont (benefit host)
- saprobe: nutrients from non-living organic material (decomposition)
- 1 gram of soil: 100 thousand fungal spores
31
Mycorrhizae
- symbiotic association between plant roots and fungi
- ectomycorrhizae and endomycorrhizae
32
What are the mutualistic benefits in mycorrhizae?
- fungi can use carbs from plant root tips: root tip produces slimy carb that helps them get into the soil
- plants benefit because they can absorb greater water/nutrients of fungi network in soil
- fungal hyphae grow wider into soil via an extensive network
33
What is the difference between ectomycorrhizae and endomycorrhizae?
- ectomycorrhizae: mostly basidiomycetes and form a mantle around root
- endomycorrhizae: hyphae penetrate plant cell walls f
34
Lichens
- symbiosis of fungi and a green algae and/or cyanobacteria
- mutualism: fungi benefit, most algae can be free-living
- can tolerate EXTREME environmental conditions
- can live on rocks, through droughts, on logs, on side of trees
35
Late blight of potato
- Irish potato famine
- the Irish migrated to Oneil, NE
- potatoes are native to Mexico and south america
- they were spread and have good growth in Ireland (main food source)
36
Rusts
- most are Basidiomycota
- most require alternate hosts
- common on cereal grains or grasses
37
Cedar apple rust
- function of alternative host
- infect junipers, junipers infect apples, apples infect junipers and cycle goes on
- allows rust fungi to overwinter on juniper
- in apple fungi in leaves and fruit
- allows for sexual recombination on the apple
38
Dutch elm
- underground root systems are connected to each other
- fungi infected the xylem and block water transport
- this spread easily because of the connected root system
39
What approaches can be used to control fungal diseases without the widespread use of fungicides?
- increase planting diversity: not planting all the same crops or plants
- not relying on one crop as a resource
