Fungi (08) Flashcards
Importance of fungi (pros)
Food source:
Edible mushrooms
Used to make food items (soy sauce, bread, blue cheese, truffles)
Used in the production of alcoholic beverages
—> Blue cheese, yeast, etc
Modern medicine/traditional medicine:
Production of some drugs (penicillin, antibiotics)
Balence/nature:
Major decomposers, therefore they break down dead or decaying organic matter into simplier substances that can be used.
–> Used for cycling nutrients throughout the biospere
Important symbiotic relationship with plants (Specifically Mycorrhizal fungi)
What are the “cons” of fungi in connection to human diseases?
1) Ring worm
–> What is it: Fungal skin infection
Symptoms:
severe itching in the groin, scalp and beard
(Moist areas is where fungi thrives)
–> many skin conditiomns can look like this, but the key feature is that it forms a ring)
Spread:
Skin-skin contact, shared objects and surfaces
Treatment: antifungal medication
2) Athletes foot (extremely common)
Nail infection
Caused by same fungus as ringworm
Risk Factors:
Use of public areas without footwear (i.e., Dirty shower floors)
Shared objects (i.e., running shoes)
Excessive sweating
3) Posioning
Eating wild mushrooms
Symtom: Abdominal pain, cramps, vomiting, and even death
Toxins in the mushroom - enter the bloodstream & affect nervous system
—> Hullcinogens, LSD, etc
What are the 5 fungi classifications?
–> Common Name
1) Mushrooms
2) Parasitic Fungi
3) Chytrids (group of fungi, that is rarely encountered)
4) Common moulds (ie molding on bread, fruits, foods, etc)
5) Yeast/truffles
Similarities of fungi and plants?
Sessile (stationary)
Multicellular, eukaryotic
Grows in ground.
Differences between fungi and plants?
Fungi are not photosynthetic
Fungi are heterotrophic, plants are autotrophic (and do photosynthesis)
Different methods of reproducing, sexual reproduction in fungi involve the fusion of specialize hypae cells, follow by meosis to produce spores. Sexual production of plants involve the production of gamates within flowers or cones.
Fungi cell wall has chitin, plant cell wall has cellulose
Fungi has NO ROOTS, fungi has mycellium, which is not ROOTS
Fungi have many nuclei per cells, plants have 1 nuclei per cell
Fungi structure
Reproductive structure = the murshroom: the visible part above the ground (THE ONLY VISIBLE PART)
Mycelium: the body of the fungus below the ground, branching networks of mesh-like filaments (IN REFERENCE TO THE NETWORK ITSELF)
—> A branch of hypae, under the soil, making up the bulk of the fungus
–> THe anchor of the fungi, keeping it in place
Hyphae: (singular/a strand: hypa) Indivdual thread-like filaments that make up the body of the fungus. each tubular structure made of cells is surrounded by cell walll (made of chitin)
–> Consitis of cytoplasm (which is continous, never ending) and** contains many nuclei **
HOWEVER,
one hypae does NOT mean one cell (each hypae has multiple nucle)
–> Each tube/thread, is seperated into cell-like compartements by cells walls called septa (/septum, that contain large pores to let material in)
–> materials can move quickly through the hypae
Note: The septum/septa, are only partially complete and contain large pores, therefore they do not COMPLETELY seperate the hypae, and therefore is refered to as “cell-like compartments”
Fungi are unable to produce with seeds
Each hypae is not quivelant to a single cell, it is a tublar strucutre made up of cells that contain multiple compartements.
How does fungi eat?
Fungi are heterotrophic, therefore they get their energy from other living or dead organismsm.
Fungi do: External Digestion (digests food externally/outside of organism) Instead of internally like a stomach or gastro-cavity
Fungi grow next to or within their food source, then release digestive enzymes into their surroundings
These enzymes digest the food and absorb the nutrients through the cell membranes of the hyphae.
As well, fungi can be multicellular and unicellular
What are the asexual reproduction methods of fungi (reproduction methods)
Asexual reproduction:
Fragmentation: Hypha breaks up into small fragments, each fragment devolpes into a new, independent, indivdual (new fungi)
Budding: Formation of a new independent fungi plant through a outgrowth/bud of the parent organismsm. Evenutally the bud detaches and becomes independent fully.
Bud/outgrowth forms on the parent cell, nucleus divides by mitosis, ensurng the bud receives a copy of the parents genetic info (+ some of the parents cyotoplasm and organnells are transfered into the devolping bud), while attached the the parent cell, it continues to devolpe its own organnells and structures, once matured, it detaches and becomes an independent organism.
How does alterations of generations work amongst fungi?
Each spore (fungi ususally produce 4) contains a haploid nucleus, when they grow/germinate, they grow into a haploid hypae (contains half the cells of a normal cells)
—> Each cell-like compartment (created by the setpum) has 1 nuclei.
–> When 2 hypae come into contact, they fuse thoughter to form a dikaryotic cell (n+n)
–> This grows into mycellium (a network of hypae), which is made of many dikaryotic cells.
–> Mycellium matures and grows into a mushroom (reproductive stuture)
–> under the mushroom cap, there is a spore-producing sturcuture called basidia.
—> 2 happloids fuse thoughter to form a diploid cell. (within the basida)
–> The diploid under goes meiosisi
—Creates 4 haploid cells that take shape as asexual femles
2 haploid nuclei fuse together forming a zygote.
–> The gtgote undergoes myosis, producing 4 haploid spores, which redos the cycle
—> Spores are structures that germinate and produce hypae.
The symbiotic relationships fungi have with the ecosystem: (Pros:)
–> Leaf cutter ants clean and chew leaves into a pulp - feed them to a fungus.
–> Fungus acts as a food source for the ants.
With protists: Fungi enveolpes and protects cynanoto bacteria or algae and supplies them with food and nutrients, these photosynthetic organismsm, supply the fungi with food.
—> Lichens are the result of the mutalistic relationship between fungi and these protists
Mycorrhiza: a symbiotic relationship between fungus and plant roots.
Fungi: Hyphae grow around/within plant roots
–> Help supply plant with nutrients (Phosphorus and Copper) and fight off harmful, soil-dwelling predators.
In exchange, the plant provides the fungus with energy rich food molecules (sugars and nutrients).
The symbiotic relationship between fungi and the ecosystem (cons)
Parasitic fungi (Cordyyceps)
Infect insect host and change its behaviour (instead of keeping ants on the ground the ants climb up high) (why? so the fungi can easily spread to other ants (more surface area)
Eventually kills the host (however, uses the host fully)
Reproductive structures grow through the body and release spores (fully takes control of the ant)
Spores (reproductive structurereleased from a high branch and dispersed widely
—> If the spores come in contact with the ant, the ant becomes infected.
How do the snails get infected?
–> The parasite goes up to its eyes, and ulses, looking like a caterpiller
this attracts birds, and when the bird eats this snail, their poop becomes infected, and the snail eats the infected poop, therefore spreading its infection/parasite.
What are the cell walls of fungi composed on?
Chitins
What can hypae look like? What does hypae form?
Hypae forms “fuzz” (food mold)
Many hypae (mycellium) forms the reproductive structure of fungi. (Mushrooms, puffballs, etc)
Hypae also forms the reproductive structure of many fungi, each structure can look verydifferent.
