Download Fungi – Notes

I. Fungi (singular – fungus) –multicellular, heterotrophs, cells have cell walls
A. Feed by releasing digestive enzymes on food, then absorbing nutrients into
their bodies (hyphae)
1. decomposers – break down dead organisms
B. Hyphae – threadlike tubes with many nuclei make up fungi bodies
(mycelium)
1. materials move through the hyphae extremely fast, there are no cell
membranes separating cells
C. Reproduce by means of spores
Can spores travel in water?
1.
2.
3.
4.
tiny, lightweight and are carried by wind
“sprout” if there are favorable conditions (food, moisture, temperature)
trillions are made and released, few survive
many people have allergies in response to spores in the air
II. Forms of Fungi (non-scientific)
A. Club Fungus – mushrooms,bracket fungi, puffballs, smuts and
rusts
(mushrooms are grown commercially, indoors, allowing
growers to control moisture, temperature, food source, and
types of mushrooms).
1. spores produced under cap in paper-like gills
B. Sac Fungus – yeasts, powdery mildews, morels, and bird’s nest
fungi
a. yeast cells can reproduce by budding – asexual
b. role in bread making, medicine, alcohol production, research
(genetic research)
C. Zygote Fungus - molds – fuzzy, shapeless, fairly flat, grow on
surface of an object(food)
1. Penicillium – kills some bacteria (antibiotics)
2. Make tofu, soy sauce, cheeses
3. Sick building syndrome – some molds that grow on
cellulose(wood), release toxins into the air that make people
sick. (stochybotry)
III. Fungi affect other organisms
A. many fungi act as parasites – harm their hosts
B. Fungicides are used to kill fungi growing on crops
CORN SMUT!
C. In addition to killing plants/animals directly via infection, many molds
produce poisons that can kill organisms that eat them, or the food they grow
on
1. alphatoxin – found on stored wheat and other food, can cause liver
cancer and death (moisture must be present).
2. ergot – grows on rye grains, causes a burning/prickling sensation,
hallucinations, convulsions, loss of feeling in limbs. There is a
connection here that has been made to the Salem witch trials.
http://www.youtube.com/watch?feature=player_detailpage&v=Mp2j2
K_FYOA#t=4s
3. fungi on animals – athlete’s foot, lung disease in poultry
(histoplasmosis), fingernail and toenail rot, ringworm,
thrush…
D. Fungus-Root Associations – mycorrhizae
1. mycorrhizae – helpful fungus-root associations (symbiosis –
mutualism)
a. help protect the plant from drought, cold, acid rain, root
diseases
b. help the plant to to get minerals from the soil
c. * the fungus gets food from the plant, digesting old cells and
sugars that come from the roots
E. Lichens
1. live in hot, dry deserts, frozen Arctic, bare rocks, wooden poles, sides
of trees, even tops of mountains
2. made of a fungus and an alga that live together – mutualism
a. fungus part of lichen provides water and minerals and a place
for algae to grow
b. algal part of the lichen uses the water and minerals to make
food for the fungus
3. lichens are often the first living things to grow on rocks and barren
areas – Pioneer organisms
4. Pioneers – lichens release acids that break apart rocks, causing cracks,
dead lichens fill the cracks providing fertile areas for other organisms
(grasses and moss) – Ecological Succession.
5. Ecological Succession – when organisms change the environment so
that other organisms can inhabit an area. In the example in number
four, above, the grasses and moss would grow and die and allow for
seeds of larger bushes and trees. Eventually, a forest would grow, and
forest animals….