Lecture 15 Flashcards
Fungi
Are Fungi eukaryotes or prokaryotes?
eukaryotes
Do fungi have cell walls?
Yes
Their cell walls are made out of what?
contains chitin
What might we call an organism that acquires nutrients by absorption
a heterotrophic organims
What do fungi secret?
exoenzymes
What are the main functions of exoenzymes?
breakdown large molecules into smaller more soluble forms that then get absorbed
Where are they released into?
into the environment
What does it mean to have an alternation of generations?
two separate, free-living organisms in the same generation
What are the name of these 2 free-living organism?
gametophyte & sporophyte
Out of gametophyte & sporophyte, which one is haploid or diploid
gametophyte -> haploid
sporophyte -> diploid
Are they unicellular?
Could be uni or even complex multicellular structures
Name a unicellular organisms & name a complex multicellular structure
uni: yeasts
multi: mushroom
What is the name of the tiny filaments that make up the bodies of fungi?
hyphae
What are hyphae used for?
greater surface area for absorption
What is a filamentous body usually hidden (below ground) called?
Mycelium
How do they disperse? (production of what?)
by producing spores (carried by wind, water)
Name a fungus which is among the largest and oldest living organisms in 1992:
The fungus Armillaria bulbosa
In 2000, tell me a couple info about the world’s s biggest fungus, discovered in Oregon’s Blue Mountains:
- more than 2400 years old
- covers area of 9.65 km^2
How do fungi reproduce? (sexually? asexually?)
BOTH
When producing asexually, mushrooms (fruiting bodies) release what?
spores (*sporulation)
How are spores dispersed?
by wind
when they land in a suitable environment what do they produce?
mycelium (underground)
When reproducing sexually, the life cycle involves the fusion of what?
fusion of hyphae from two individuals
What do we call the fusion of hyphae from two individuals?
plasmogamy
So what is more specifically plasmogamy?
forming a mycelium that contains haploid nuclei of both individuals
eventually, the 2 nuclei will fuse to form what?
a diploid zygote
Through what process can it then produce four haploid cells?
meiosis
Some have alternation of generations, what does this mean?
independent haploid life stage alternating with diploid stage
(Like some plants and protists)
What is the Primary role of fungi in ecosystems?
Decomposers
Many species are involved in many things:
- break down wood & leaves
- some nutrients absorbed & used
- rest returns to soil recycled by plants
They can break down most of what?
organic compounds
Can fungi be pathogens?
Yes, Some cause disease in plants reduce yield or kill plants
Give a few examples of fungi that are pathogens for plants:
fruit - especially berries + vegetables: potatoes, root crops, corn, grain
Can fungi be pathogens for animals?
yes, some cause disease in animals including humans
Give a few examples of fungi that are pathogens for animals:
Athlete’s foot, Jock itch, Yeast infections, Nail infections and respiratory diseases (ex.mold problems in hospitals, schools)
+ Aspergillus (lungs)
Fungi in building, toxigenetic fungi produce what?
mycotoxins
Do mycotoxins invade tissues?
no
What carry the toxins? (vehicles for their inhalation)
spores + mycelial
Can fungi be a mutualistic symbionts?
yes, some form mutualisms
Name one important mutualism
lichen
What is the association of lichen?
association between a fungus and a green algae
(or cyanobacteria)
How are they considered a mutualistic symbionts?
algae provides food (organic carbon)
+ fungus provides with a suitable physical environment for growth
Why do we say they are Important pioneers?
because they can break down rock into soil
Their main food source is for whom?
for mainly caribou and reindeer
What is another mutualism?
mycorrhizae
What are the 2 associations for mycorrhizae?
Association between a fungus and a plant
Where do you find mycorrhizae?
found on roots of over 90% of all vascular plants
What makes them Mutualistic Symbionts?
Fungus acquires carbon from plant
+
plant gets nutrients, water, minerals,
pathogen resistance increased
resistance to toxic elements in the
soi
How does Mycorrhizal fungi
extend the volume of soil?
by the root system (fungus = yellow hyphae)
Mycorrhizal fungi produce enzymes, what are their main function?
solubilize nutrients (aid in nutrient uptake)
What are Group of achlorophyllous plants?
unable to photosynthesize and produce carbohydrates
Do they have chlorophyll?
nope
How do parasitic plants obtain their carbon?
from trees
Alchlorphyllous use mycorrhizas to do what? (2)
- to obtain minerals and nutrients
- to tap the carbon supplies of nearby plants via their roots
So some fungi in forest soils form mycorrhizal associations with what? (2)
- Trees and achlorophyllous species
- Carbohydrates pass from conifer to the achlorophyllous plants
How do Carbohydrates pass from the conifer to the achlorophyllous plants?
via their common mycorrhizal partner
What 2 very important economic uses of fungi?
- food
- antibiotics
Hoe could they be important for food?
- supermarket mushrooms, morels, truffles
- ripen some cheeses: Brie, Camembert
- others for flavor of cheese: Stilton, Gorgonzola
which are dangerous?
Amanita = deadly
Complete the sentence:
most _______ are fungi, slime & water ______ are protists!
most molds are fungi, slime & water molds are protists!
Is yeast a fungi?
yes
Is yeast uni or multicellular?
it’S uni
Name 2 ways the cells may divide:
- binary fission
- by budding
Where is yeast used?
In bread making, carbon dioxide is the important product, with the evolving gas causing the bread to rise.
* In beer and wine-making, alcohol is the important product of yeast, though carbon dioxide may also be used in beer and champagne.
= BREAD AND BEER (B&B)
What is the second way fungi are economically important?
antibiotics
How come they can be antibiotics?
Produce chemicals that kill them = Antibiotics
Many fungi are natural enemies of bacteria, name one (you know this one):
Penicillin!!
RECAP: what are the 3 main ecological roles of fungi:
- decomposers
- pathogens
- mutualistic symbionts
