Intro, Fungal Structure, and Chytridiomycetes Flashcards
The seven kingdoms of life
Archaebacteria, Eubacteria, Protozoa, Chromista, Eumycota, Plantae, Animalia
Characteristic of fungi that distinguishes them from plants
Fungi do not contain chlorophyll
Characteristic of fungi that distinguishes them from animals
Fungal cells are typically surrounded by cell walls
How do fungi obtain nutrients?
Absorptive nutrition: Digestive enzymes are secreted through the porous hyphal wall and nutrients are absorbed back through the pores.
How was Otzi using the fungi found in his belt?
He was using it to treat his parasitic whip worm infection.
The genus and species of the fungus used by Otzi
Piptoporous betulinus, a bracket fungus that contains polyporenic acid.
Fox Fire
Mentioned by Aristotle, the bioluminescent fruiting bodies of fungi that were used by soldiers to mark their paths at night.
Benefits of fungi
They are sources of medicine, aid in food production, and increase disease and drought resistance in plants.
Negatives of fungi
The cause of diseases, such as St. Anthony’s fire; are the number one pathogen of plants; are the most common source of food rot.
Appressorium
A flattened, hyphal “pressing” organ that is used to puncture the outer layer of the host using turgor pressure.
The fungus found on bananas that creates brown spots and facilitates ripening
Colletotrichum musae
“Fungus humongous”
Armillaria ostoyae, which is believed to be 8650 years old.
Both positive and negative interactions; simply implies a relationship
Symbiosis
A relationship where both parties benefit
Mutualism
One party benefits, the other sees little or no effect
Commensalism
One party benefits, the other is harmed
Parasitism
What is fungi’s major job for the planet?
They are the major recyclers for the planet; they spin the carbon cycle
How have fungi been used to create a plastic-like material?
Using a 3-D printer, ground up trash and fungus are used to synthesize an object. It is then incubated in a moist chamber until the fungus have digested the trash and replaced it with mycelia. The object is then baked to kill the fungus, drying it down to a lightweight, sturdy material.
The 7 official phyla and zygomycetes
Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, Microsporidia, Glomeromycota, Zygomycetes, Ascomycota, Basidiomycota
Two phyla containing 90% of all fungi
Ascomycetes and Basidiomycetes
Phylum characterized by having basidia
Basidiomycetes
Phylum characterized by having asci
Ascomycetes
Phylum characterized by making zygospores
Zygomycetes
Phylum characterized by having arbuscular, endomycorrhizal fungi
Glomeromycetes
Phylum characterized by having a single or no flagella
Chytridiomycetes
Phylum characterized by containing chytrids with sporic meiosis
Blastocladiomycetes
Pylum characterized by having anaerobic, multiflagellated chytrids
Neocallimastigomycetes
Phylum characterized by being obligate, intracellular parasites
Microsporidia
The body or vegetative structure of a fungus
Thallus
A tube with a rigid wall that contains a moving slug of protoplasm and only grows at the tip
Hyphae
A mat of hyphae
Mycelium
The structure of a mold
A multicellular mass comprised of mycelia
What is a yeast?
A single-celled, microscopic fungi
The current model of hyphal growth
Actin motor proteins run along microtubule “tracks” to deliver vesicles from the rough ER and golgi to the plasma membrane at the apex, increasing the size of the membrane.
The most common ancestor or both fungi and animals
Choanoflagellates
The three crown eukaryotes
Animals, Fungi, and Plants
Purpose of fungal spores
An efficient mechanism for dispersal for replication
Fusion
Anastamosis
How do nuclei migrate in hyphal fungi and in what direction do the go?
Nuclei migrate with the help of microtubules and they move towards the hyphal tip.
How do fungi create tissue-like structures despite their limitation of growth in one direction?
Through branching and anastamosis
When, in a growth curve, are fungus most likely to create spores:
the stationary phase
dimorphic
“Two shaped”; many fungi that grow as yeasts have the ability to form true hyphae under the appropriate conditions.
What distinguishes a germ tube from true hyphae
Germ tubes have a septum separating them from the mother cell. True hyphae do not have this.
What is the major difference between yeast cell walls and hyphal cell walls
Yeast cell walls contain mannan on the outside, which filamentous fungi do not have
What is a birth scar on the mother cell
it is the leftover primary septum that is left behind when the daughter cell pops off
How do fission yeast divide?
fission yeast are cylindrical and develop their septum in the middle of the cell
Most yeast are
ascomycetes
Two examples of ascomycete yeasts
Saccharomyces cerevisiae and Candida albicans
Name a yeast that is a basidiomycete
Cyrptococcus neoformans
Chytrid rhizoids vs. hyphae
Rhizoids anchor the thallus to the substrate and do not contain nuclei or septa. Hyphae do have nuclei and septa.
Three phyla considered “true chytrids”:
Chytridiomycetes, Blastocladiomycetes, Neocallimastigomycetes
What is the defining characteristic of chytrids that no other fungi have
motile zoospores with a whip-like flagellum at the rear
Where are chytridiomycetes found in nature
Moist soils and aquatic environments
Three roles of Chytridiomycetes in nature
Decompose particulate organic matter, parasitic of plants and animals, and zoospores are food for zooplankton
What are pseudopods
a secondary method of chytrid motility, the crawling is a searching behavior for food or a place to encyst.
Chytrid that is parasitic of nematodes
Catenaria anguillulae
Purpose of rhizoids in chytridiomycetes
Allow the fungus to attach to a substrate, secrete digestive enzymes, absorb nutrients, and have no nuclei
The chytrid that causes wart disease in potatoes
Synchytrium endobioticum
zygotic meiosis
identical haploid individuals fuse to form a diploid zygote, which susequently undergoes meiosis
What distinguishes the HAPLOID infection in potato wart disease
A “summer spore” is formed, is not readily visible
What distinguishes the DIPLOID infection in potato wart disease
A large “resting spore”, or wart, is formed
The Chytridiomycete that is parasitic to frogs
Batrachochytrium dendrobatidis
How does Batrachochytrium cause disease in frogs
the fungus colonizes the keratinized epithelium of frogs, causing a fatal inflammatory response
What is the likely reservoir for Batrachochyrium
The larval stage of the amphibian
Two examples of Chytridiomycetes
Synchytrium endobioticum and Catenaria anguillulae
The phylum of Chytrids that undergoes SPORIC meiosis
Blastocladiomycetes
Sporic meiosis
alternation of generations; Male and Female gametangia are formed, then fuse to form the diploid phase.
How do male Allomyces find female Allomyces
The females secrete sirenin, which induces the males, who have sirenin receptors, to swim to them.
Thick-walled Allomyces sporangia
undergo sporic meiosis, producing haploid zoospores
Thin-walled Allomyces sporangia
Produce diploid zoospores that grow into more diploid thallus
Example of a Blastocladiomycete
Allomyces arbusculus
The defining characteristics of Neocallimastigomycetes
Polyflagellates, anaerobic, have a hydrogenosome to generate ATP
Where are Neocallimastigomycetes found
in the stomachs of rumens
What is a hydrogenosome
a degenerate mitochondria which generates ATP via fermentation, followed by NADH losing an electron to hydrogenase, converting it to NAD+
What is the role of rhizoids in Neocallimastigomycetes
They penetrate plant material in the gut and secrete enzymes that efficiently break down cellulose
How are neocallimastigomycetes passed from one animal to another
Through cysts in their feces
