Fungi Flashcards
What 2 ways do fungi live?
As decomposers and symbionts
Why can fungi live as decomposers and symbionts?
Because they absorb their nutrition
How has fungi evolved that has allowed them to survive absorbing their nutrition?
Extensive surface are and rapid growth
How do fungi reproduce?
Sexual and asexual reproduction that releases spores
What stage does many fungi have?
Heterokaryotic - reproductive where more than 1 nuclei (from different separate mating types) is present w/in same cytoplasm
What are the 4 ways in which fungi differ from eukaryotes?
1- nutrition mode
2- structural organization
3- growth
4- reproduction
What is it called when fungi (like animals) require their nutrition from absorption?
Heterotrophic
What do fungi use to help breakdown food surrounding it so it can absorb the simpler compounds?
Exoenzymes - powerful hydrolytic enzymes secreted outside
What are the 3 roles of fungi play due to their absorption of nutrients?
1- saprobic (decomposer)
2- parasitic
3- mutualistic
Explain Saprobic as a role fungi play due to their absorption of nutrients
(Decomposers) Fungi absorb nutrients from nonliving organisms
Explain Parasitic as a role fungi play due to their absorption of nutrients. What can some be?
Fungi absorb nutrients from the cell of living hosts - some infecting humans and plants can be pathogenic
Explain Mutualistic as a role fungi play due to their absorption of nutrients
Fungi absorb nutrients from host organism but they also give back with functions that benefits their partner/host in some way
Explain the bodies of fungi (2)
Vegetative bodies constructed of tiny filaments = hyphae
When hyphae are interwoven mat = mycelium
What does the fungi filament hyphae have? What is it mainly built from?
Have cell walls
Built mainly from chitin
What are the cell walls in hyphae also be called?
Septa
Though hyphae have septa/cell walls they are not completely closed off from neighboring cells. Why?
They have pores so ribosomes/mitochondria/etc can flow between cells
What is fungi called when it lacks septa? Explain
Coenoytic = consists of continuous cytoplasmic mass with load of nuclei
What does parasitic fungi have some of their hyphae modified into?
Haustoria = nutrient absorbing hyphal tips that penetrate the tissue of their host
If fungi use sexual and asexual reproduction to produce spores that then are released, what is relied on to move the spores?
Water and wind
What happens to fungi spores when they land in a moist place?
Germinate to produce mycelia - if food is around the area
What are most spores and hyphae of fungi?
Haploid
Does fungi have a diploid stage?
Yes - During the sexual life cycles
What happens genetically to some mycelia in fungi? Called?
Fusion of 2 hyphae with still 2 genetically different nuclei = heterokaryotic mycelium
In the sexual life cycle of fungi, what is karyogamy?
Fusion of haploid nuclei of 2 different “parents”
In the sexual life cycle of fungi, what is plasmogamy?
When the cytoplasm of the 2 “parents” fuse = becomes heterokaryotic mycelium
Describe the asexual reproduction of fungi (4)
Mycelium develop store-producing structures
Spores are released
Spores germinate
Become new mycelium
Describe the sexual reproduction of fungi (5)
Within Mycelium hyphae will go through plasmogamy (cytoplasm fuse) = heterokaryotic stage
Karyogamy will happen (fusion of nuclei) = zygote
Meiosis = spore producing structures
Spores released
Germination of spores = mycelium
How many phylums are in fungi?
4
What are the 4 phylums of fungi?
1- Chytridiomycota
2- Zygomycota
3- Ascomycota
4- Basidiomycota
When did fungi start appearing on land?
Around the same time plants did
What did the first forms of fungi look like?
Aquatic flagellated organisms
Where are the phylum Chytridiomycota found?
Mainly aquatic
What 2 roles does the phylum Chytridiomycota live in environments?
Saprobes = Decomposers
Parasitic - to protists, plants and animals
Where is the phylum Zygomycota found?
Terrestrial living in soil or on decaying plant/animal
What is one Zygomycota group? What do they do?
Mycorrhizae - have mutualistic relationship with plant roots
What can be said about the hyphae in the phylum Zygomycota?
Lack septa so it is coenocytic fungi
Does the phylum Zygomycota have any septa if they are coenocytic?
Found only in reproductive structure
What is another example of the phylum Zygomycota? Common name?
Rhizopus stolonifer - black bread mold
How does the Rhizopus stolonifer the phylum Zygomycota form?
Horizontal hyphae spread out over food, penetrates it and digest its nutrients
What structure develops in the asexual reproduction of the Rhizopus stolonifer the phylum Zygomycota?
100’s of haploid spores develop in sporangia at tips of hyphae
What makes the Rhizopus stolonifer the phylum Zygomycota reproduce sexually?
When environmental conditions worsen
What 2 structures develop in the sexual reproduction of the Rhizopus stolonifer the phylum Zygomycota?
Plasmogamy (cytoplasm fusion of 2 mating types) produce a zygosporangium
Inside heterokaryotic fuse to form diploid nuclei and undergo meiosis
Describe the asexual reproduction of the Rhizopus stolonifer the phylum Zygomycota from start to end (4)
Mycelium will produce/grow sporangia
Spores are produced in sporangia
Spores get released
Spores germinate into mycelium
Describe the sexual reproduction of the Rhizopus stolonifer the phylum Zygomycota from start to end (8)
2 mycelia match up
Between them produce gametangia w/ haploid nuclei
They undergo plasmogamy to produce zygosporangium = heterokaryotic structure
When the nuclei fuse = karyogamy
Forms a diploid nuclei which undergoes meiosis
Sporangia grows producing spores
Spores are released and germinate
Mycelia grows
What is the phylum Ascomycota known as? Why?
Sac fungi - produces spores in saclike asci
What kind of spores are produced in the asci of the Ascomycota?
Sexual
Where are the asci collected in the phylum Ascomycota? Called?
Collected in macroscopic bodies called ascocarp
What are 2 examples of of an ascocarp of the phylum Ascomycota?
The edible parts of truffles and morels
What structure develops in the asexual reproduction of the phylum Ascomycota?
Produces a large number of asexual spores which disperse in wind
Explain the spores that are produced asexually by the phylum Ascomycota. What are they called?
Naked spores - called conidia
Where does the conidia (naked spores) that are produced asexually by the phylum Ascomycota develop? Called?
Develop in long chains or clusters at tips of specialized hyphae - called conidiophores
Describe the asexual reproduction of the phylum Ascomycota from start to end (4)
Mycelium develop specialized hyphae called conidiophores
Conidiophores produce conidia (naked spores)
Conidia are released
They germinates and grow into mycelium
Describe the sexual reproduction of the phylum Ascomycota from start to end (9)
2 mycelia match up
One has ascogonium other antheridium
They undergo plasmogamy to produce an ascocarp
Has heterokaryotic asci
When the nuclei fuse in ascus = karyogamy
Forms a diploid nuclei which undergoes meiosis
The asci produces ascospores
Spores are released and germinate
Mycelia grows
What is the phylum Basidiomycota known as? Why?
Club fungi - shaped like a club
What are 4 examples of the phylum Basidiomycota?
Mushrooms, shelf fungi, puffballs and rusts
What is the name of the phylum Basidiomycota derived from?
Basidium = long diploid stage
What role does the phylum Basidiomycota?
Saprobic = Decomposers
What are the 2 groups of the phylum Basidiomycota?
Rusts and smuts
Explain the sexual life cycle of the phylum Basidiomycota (8)
Haploid mycelia match up Undergo plasmogamy Produces heterokaryotic mycelium Forms Basidiocarp Undergoes karyogamy Produces diploid nuclei undergoes meiosis Basidium produces Basidiospores These disperse and germinate into mycelium
What are the 4 keys features for the 4 phylums?
Chytridiomycota - motile spores with flagella
Zygomycota - zygosporangium in sexual reproduction
Ascomycota - spores in asci sacs
Basidiomycota - spores in Basidium
