Transcript Kingdom Fungi - Dr. Annette M. Parrott

Kingdom Fungi
• The word Fungus comes from
Latin word meaning sponge.The
plural of fungus is fungi.
• Like plants,fungi often grow in
soil but they cannot make food
from sunlight.
• The stalk and the head of the
toadstool are the fungi's
fruiting body .This releases tiny
spores.New fungus grow from
these.Fungi begin to reproduce
when one mass of underground
threads meet another (+ & strains) of the same species
they grow and produce a new
fruiting body.
Classification by Reproduction
• People used to think that
fungi were plants. But
because they are absorptive
heterotrophs they are not
producers and are consumers
instead
• They have cell walls made of
chitin--a polysacchride like
sugar or starch (instead of
cellulose in plant cells)
• Fungi are classified by how
they reproduce. They
produce ascospores (yeast)
basidiospores, (mushrooms) ,
zygospores (bread mold),
fungi imperfecti (yeast
infections)
Fruiting body refers to
the mushroom itself, a
reproductive structure.
Hyphae are the basic
Hyphae may contain
internal crosswalls,
called septa, that
divide the hyphae
into separate cells.
Coenocytic hyphae
lack septa. The
septa of many
species have pores,
allowing cytoplasm
to flow freely
from one cell to
the next.
Cytoplasmic
movement within
the hypha provides
a means to
transport of
materials.
structural unit of a fungus
made up of branching
filaments.
Hyphae form a tangled
network of fibers
called a Mycelium.
Division (Phylum) Zygomycota
• molds, Rhizopus (bread mold)
• Asexual reproduction , like Rhizopus, produces a
growth pattern resembling that of the
strawberry. Long hyphae called stolons run along
the surface of their food, periodically sinking
down root-like projections called rhizoids. Long
stalks called sporangiophores arise from the
stolons, bearing tiny round sporangia, which break
open to release spores.
Division (Phylum) Ascomycota
• sac fungi (yeasts, morels, truffles, Dutch
elm disease, chestnut blight, ergot)
• Ascomycetes have a wide range of body
forms, from the single-celled yeasts to
mushroom-like morels. The mushroom-like
fruiting body is called an ascocarp. Yeasts
form tiny buds that break off and grow into
larger cells.
• Ergot fungi infests rye bread and other
grains. This fungus has altered the course
of human history in areas like Russia where
it is widespread. People eating infected rye
bread were thought to have been possessed
by the devil, b/c of their wild dancing and
uncontrolled behavior. We know now that
the chemical causing this behavior is none
other than LSD.
Division (Phylum) Basidiomycota
• club fungi (mushrooms, puffballs, shelf
fungi, rusts, smuts)
• Basidiomycetes, form a basidiocarp, the
fruiting body commonly called a mushroom.
The underside of the mushroom cap is
filled with thin plates called gills.
• Most of the body of a basidiomycete is
actually growing under the ground. Because
the hyphae of basidiomycetes grow at
roughly equal rates from the center of
growth, mushrooms often appear in a large
circular ring. called fairy rings.
• The largest organism on the planet is a
single large fungus, a root parasite, which
extends underneath 2,200 acres of conifer
forest in Oregon’s Blue Mountains. It is at
least 2,400 years old.
• Life Cycle of a Mushroom
Fungi Imperfecti (Deuteromycota)
• Penicillium, Aspergillus
• This “catch-all category” contains many
species of fungi which have never been
observed to reproduce sexually, and
cannot, therefore, be classed in the
other three Divisions, although most of
these are probably different species of
ascomycetes. They reproduce asexually
in a manner similar to ascomycetes, with
hyphae called conidiophores
fragmenting into numerous
conidiospores. Penicillin and Aspergillus
are typical fungi imperfecti.
• Discovery of Penicillin
Fungi Life Cycle
In general, the life cycle involves the
fusion of hyphae from two
individuals, forming a mycelium
that contains haploid nuclei of
both individuals.
The fusion of hyphae is called
plasmogamy.
The fused hyphae containing haploid
nuclei from two individuals is
heterokaryotic.
In some cases, plasmogamy results in
cells with one nucleus from each
individual. This condition is called
dikaryotic.
Eventually, two nuclei that originated
from different individuals fuse to
form a diploid zygote.
Meiosis then produces either four
haploid nuclei or four haploid cells.
Basidiomycota
Ascomycota
Zygomycota
Harmful Fungi
• Many mushrooms are poisonous,
hallucinogens and even fatal
(Amanita--> death cap)
• Many fungi are parasitic and
cause diseases like ringworm,
athletes foot,
• Can rot and contaminate foods
• Can destroy almost every type
of product or food aside from
some plastics
• Black Mold in Buildings
• Building a House: Recipe for
Disaster
Beneficial Fungi
• The mycorrhizal fungi live as
partners with plants, helping them
absorb nutrients
• People eat mushrooms, truffles and
other fungi, citric acid in Coke
• Fungi are decomposers like bacteria
and help to recycle organic matter to
inorganic = saprophytic
• Yeasts are used in making bread,
wine, beer, solvents, cheese.
• Drugs made from fungi cure diseases
and stop the rejection of
transplanted hearts and other
organs.
• Fungi are also grown in large vats to
produce flavorings for cooking,
vitamins and enzymes for removing
stains.
• Beneficial Protists & Fungi
Mycorrhizae
Mutualistic association of plant roots and fungi
increase the absorptive surface area of plant roots.
(Fungus gets organic nutrients from plant; Plant gets
minerals from the soil via the fungus).
Over 95% of
vascular
plants have
mycorrhizae
Lichens are a symbiotic
association between
algae and fungi.
Figure 31.12 Arthrobotrys, a predatory deuteromycete (imperfect fungus)
Some fungi are predatory.
Many fungi are decomposers.
Saprobes.
Turkey tail fungus, Trametes versicolor
Tom Volk, University of Wisconsin-La Crosse
Fungi Links
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Fun Facts About Fungi:
Microbe Fungi:
Amazing Kingdom of Fungi:
Fungi Tutorial:
Fungi Classification:
Campbell’s Chapter 31: Fungi
Biology Junction Notes
Fungi Quizzes