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Kingdom Fungi
FUNGI ARE A GROUP OF LIVING
ORGANISMS HAVING A BODY CALLED
MYCELIUM MADE UP OF HYPHAE,
WHICH ARE THE COENOCYTIC (MULTI
NUCLEATED)
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Characteristics
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THE CHARACTERISTICS OF FUNGI
Non photosynthetic
Non chlorophyllous
Eukaryotes
Non motile
Most are saprobes
(live on dead
organisms)
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THE CHARACTERISTICS OF FUNGI
Absorptive
heterotrophs
(digest food first & then
absorb it into their bodies
Release digestive enzymes to
break down organic material
or their host
Store food energy as
glycogen
BREAD MOLD
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THE CHARACTERISTICS OF FUNGI
Important
decomposers
Most are multicellular,
except unicellular yeast
Lack true roots, stems
or leaves
MULTICELLULAR
MUSHROOM
UNICELLULAR YEAST
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THE CHARACTERISTICS OF FUNGI
Cell
walls are made of chitin
(complex polysaccharide)
Body is called the Thallus
Grow as microscopic tubes
or filaments called hyphae
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THE CHARACTERISTICS OF FUNGI
Some
fungi are internal or
external parasites
A few fungi act like predators &
capture prey like roundworms
Predaceous
Fungi feeding on
a Nematode
(roundworm)
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THE CHARACTERISTICS OF FUNGI
Some
are edible, while others
are poisonous
EDIBLE
POISONOUS
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•Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for at
Parasites
- feeding on
living tissue of a host.
Parasites
that cause
disease are called
pathogens.
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THE CHARACTERISTICS OF FUNGI
Produce
both
sexual and
asexual spores
Classified by
their sexual
reproductive
structures
Spores come
in various
shapes
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THE CHARACTERISTICS OF FUNGI
Grow
best in warm, moist
environments
Mycology is the study of fungi
Mycologists study fungi
A fungicide is a chemical used to
kill fungi
Fungicide
kills leaf
fungus
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THE CHARACTERISTICS OF FUNGI
Fungi
include
puffballs, yeasts,
mushrooms,
toadstools, rusts,
smuts, ringworm, and
molds
The antibiotic
penicillin is made by
the Penicillium mold
Penicillium mold
Puffball
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AGARICUS ( MUSHROOM)
Some species of
agaricus are
commonly
cultivated as a
food, for example,
the button
mushroom,
Agaricus
campestris.
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An effort is being made to
increase the cultivation of
additional species of
mushrooms, specialy in Asia.
Some can be grown on
waste products. Many have
high protein content.
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DIFFERENCE BETWEEN FUNGI & PLANT
The (carbohydrate) molecule used to
store energy in fungi is glycogen.
Glycogen is also used to store energy
in the muscle and liver cells of animals
but plants have a different storage
molecule, called starch.
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Fungi are achlorophyllous, which means
they lack the chlorophyll pigments present
in the chloroplasts in plant cells and which
are necessary for photosynthesis. Fungi
are therefore incapable of
photosynthesis
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The Importance of Fungi
USEFULL FUNGI
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FOOD
Fungi are also important directly as food
for humans. Many mushrooms are edible
and different species are cultivated for
sale worldwide.
While this is a very small proportion of the
actual food that we eat, fungi are also
widely used in the production of many
foods and drinks.
These include cheeses, beer and wine,
bread, some cakes, and some soya bean
products.
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MEDICINES
Penicillin, perhaps the most famous
of all antibiotic drugs, is derived
from a common fungus called
Penicillium.
Many other fungi also produce
antibiotic substances, which are now
widely used to control diseases in
human and animal populations.
The discovery of antibiotics
revolutionized health care
worldwide.
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SOIL FERTILITY
They maintain the soil
fertility by decomposing
the dead organic matter.
E.g
Mycorrhizal Fungi
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HAMRFUL FUNGI
FOOD SPOILAGE
The fungi which make our bread
and jam go mouldy are only
recycling organic matter, even
though in this case, we would
prefer that it didn't happen!
Fungal damage can be
responsible for large losses of
stored food, particularly food
which contains any moisture
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HUMAN DISEASE
Fungi cause a number of
diseases in human beings
like aspergillosis (ear,
lungs diseases)
moniliases (skin, mouth,
gums diseases)
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PLANT DISEASE
Spore production
and dispersal is
enormously
efficient in fungi
and plants of the
same species
crowded together
in fields are ripe
for attack.
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Vegetative Structures
NON-REPRODUCTIVE
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•Hyphae can grow and form a
network called a mycelium.
When a mycelium reaches a
certain size (the size depends on
the species of the fungus), it
begins to form structures
called sporangia
whose function is to
release spores
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HYPHAE
Tubular
shape
ONE continuous
cell
Filled with
cytoplasm & nuclei
Multinucleate
Hard cell wall of
chitin also in insect
exoskeletons
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HYPHAE
Stolons –
horizontal hyphae
that connect
groups of hyphae
to each other
Rhizoids – rootlike
parts of hyphae
that anchor the
fungus
STOLON
RHIZOIDS
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HYPHAE
Cross-walls
called
SEPTA may form
compartments
Septa have pores
for movement of
cytoplasm
Form network called
mycelia that run
through the thallus
(body)
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ABSORPTIVE HETEROTROPH
Fungi get carbon from organic sources
Tips of Hyphae release enzymes
Enzymatic breakdown of substrate
Products diffuse back into hyphae
Nucleus “directs” the digestive
process
Digested material is then used by
the hypha
MODIFICATIONS OF HYPHAE
Fungi
may be classified based on
cell division (with or without cytokinesis)
Aseptate or coenocytic (without septa)
Septate (with septa)
NO
CROSS
WALLS
CROSS
WALLS
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MODIFICATIONS OF HYPHAE
HAUSTORIA – parasitic
hyphae on plants &
animals
Septate Hyphae Coenocytic Hyphae
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HYPHAL GROWTH
Hyphae
grow from their tips
Mycelium is an extensive, feeding
web of hyphae
Mycelia are the ecologically active
bodies of fungi
This wall is rigid
Only the tip wall is plastic and stretches
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REPRODUCTIVE STRUCTURES
ASEXUAL & SEXUAL SPORES
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REPRODUCTION
Most
fungi reproduce Asexually and
Sexually by spores
ASEXUAL reproduction is most
common method & produces
genetically identical organisms
Fungi reproduce SEXUALLY when
conditions are poor & nutrients
scarce
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SPORES
Spores
are an adaptation to life on
land
Ensure that the species will
disperse to new locations
Each spore contains a reproductive
cell that forms a new organism
Nonmotile
Dispersed by wind
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SEXUAL REPRODUCTION
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SEXUAL REPRODUCTION
Used when environmental
conditions are poor (lack
of nutrients, space,
moisture…)
No male or female fungi
Some fungi show
dimorphism
May grow as MYCELIA
or a YEAST –LIKE
state (Filament at 25oC
& Round at 37oC)
Dimorphic Fungi
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SEXUAL REPRODUCTION
Haploid 1n hyphae from 2 mating types
(+ and -) FUSE (Fertilization)
Forms a hyphae with 2 nuclei that
becomes a ZYGOTE
The zygote divides to make a SPORE
+
SPORE FORMS
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ASEXUAL REPRODUCTION
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THREE TYPES OF ASEXUAL REPRODUCTION
Fragmentation – part of the mycelium
becomes separated & begins a life of its
own
Budding – a small cell forms & gets
pinched off as it grows to full size
Used
by yeasts
Asexual spores – production of spores by
a single mycelium
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REPRODUCE BY SPORES
Spores may be Formed:
Directly
on hyphae
Inside sporangia
On Fruiting bodies
Penicillium
hyphae
Amanita fruiting body
Pilobolus sporangia
ASEXUAL REPRODUCTION
Fruiting
Bodies are modified hyphae
that make asexual spores
An upright stalk called the
Sporangiosphore supports the spore
case or Sporangium
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ASEXUAL REPRODUCTION
Types
of
Fruiting Bodies:
Basidia
Sporangia
Ascus
Sporangia
Basidia
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Fruiting Bodies
Both are
composed
of hyphae
mycelium
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HYPHAL GROWTH FROM SPORE
Germinating spore
mycelium
Mycelia have a huge surface area
More surface area aids digestion &
absorption of food
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Evolution of Fungi
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CLADOGRAM
Which of the
following is most
closely related
to a mushroom
(fungus)?
WHY?
Recent DNA-based
studies show
that fungi are
more similar to
animals than to
plants
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Evolution of the Fungi
IT’S ALL ABOUT THE SPORES!
Fungi
are classified by their
REPRODUCTIVE STRUCTURES and
SPORES
The
reproductive structures are:
BASIDIA - BASIDIOMYCOTA
SPORANGIA - ZYGOSPORANGIA
ASCUS - ASCOMYCOTA
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IT’S ALL ABOUT THE SPORES!
Spores
are made of:
Dehydrated cytoplasm
Protective coat
Haploid cell
Wind,
animals, water, & insects
spread spores
Spores germinates when they land
on a moist surface (new hyphae
form)
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asci
zygosporangia
motile spores
basidia
Classification
& Phylogeny
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Major Groups of Fungi
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MAJOR GROUPS OF FUNGI
Within the past
few years, several
groups have been
re-classified into
the protists
Two of these
groups are the
slime molds and
water molds
Classification by Nutrition
Saprobes
Decomposers
Molds,
mushrooms, etc.
Parasites
Harm
host
Rusts and smuts (attack plants)
Mutualists
Both
benefit
Lichens
Mycorrhizas
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MAJOR GROUPS OF FUNGI
Basidiomycota
– Club Fungi
Zygomycota – Bread Molds
Chytridiomycota – Chytrids
AM Fungi - Mycorrhizas
Ascomycota – Sac Fungi
Lichens – Symbiosis (algae & Fungi)
ZYGOMYCOTA
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ZYGOMYCOTA
Called the sporangium
fungi
Commonly called molds
Also includes blights
Hyphae have no cross
walls (aseptate)
Grow rapidly
Includes bread mold
Rhizopus stolonifer
Rhizopus on strawberries
Tomato Blight
•Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for at
ZYGOMYCOTA
Asexual reproductive structure called
sporangium atop sporangiospores make
spores
Rhizoids anchor the mold & release
digestive enzymes & absorb food
Stolons connect the fruiting bodies
ZYGOMYCOTA
Sexual spores are produced by
conjugation when (+) hyphae and (-)
hyphae fuse
Sexual spores are called ZYGOSPORES
Zygospores can endure harsh
environments until conditions improve
zygospore
BASIDIOMYCOTA
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BASIDIOMYCOTA
Called Club fungi
Includes:
Mushrooms
Toadstools
Bracket
& Shelf fungi
Puffballs
Stinkhorns
Rusts and smuts
USES FOR BASIDIOMYCOTA
Some are used as
food (mushrooms)
Others damage
crops (rusts &
smuts)
Corn Smut
Portobello Mushrooms
Soybean
Rust
CHARACTERISTICS OF CLUB FUNGI
Seldom reproduce asexually
The visible mushroom is a fruiting body
Basidiocarp (fruiting body) is made of a
stalk called the stipe and a flattened
cap with gills called Basidia underneath
Basidiospores are found on basidia
Annulus is a skirt-like ring around some
stipes
Vegetative structures found below
ground
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Hyphal fusion mycelium and fruiting
of haploid
body are dikaryotic
mycelia
haploid
mycelium
MUSHROOM
LIFE CYCLE
N
Meiosis
2N
N+N
Nuclear
fusion in
basidium
young basidia - the
only diploid cells
Fig 31.12
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ASCOMYCOTA
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CHARACTERISTICS
Called Sac fungi
Includes Cup fungi, morels, truffles,
yeasts, and mildew
May be plant parasites (Dutch elm
disease and Chestnut blight)
Reproduce sexually & asexually
Ascus - sac that makes ascospores in
sexual reproduction
Specialized hyphae known as Ascocarps
contain the asci
CHARACTERISTICS
Yeasts
reproduce
asexually by budding
(buds break off to
make more yeast
cells)
Asexual spores called
conidia form on the
tips of special hyphae
called conidiophores
CONIDIA
CONIDIA FORMATION
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YEASTS BUDDING
Saccharomyces
USES OF ASCOMYCETES
Truffles and morels are
good examples of edible
ascomycetes
Penicillium mold makes
the antibiotic penicillin.
Some ascomycetes also
gives flavor to certain
cheeses.
Saccharomyces
cerevesiae (yeast) is used
to make bread rise and
to ferment beer & wine.
CHYTRIDIOMYCOTA
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CHYTRIDIOMYCOTA
Called
chytrids
Produce motile
spores
Mostly saprobes
and parasites in
aquatic habitats
Biodegrade and
recycle nutrients
Chytrid that attacks Potatoes
MYCORRHIZA
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MYCORRHIZAS
Fungus associated with plant roots
Mutualism between:
Fungus
(nutrient & water uptake for plant)
Plant (carbohydrate for fungus)
Several kinds:
Zygomycota
– hyphae invade root cells
Ascomycota & Basidiomycota – hyphae
invade root but don’t penetrate cells
Extremely important ecologically
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LICHENS
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LICHENS
Mutualism between:
Fungus
(structure)
Algae or cyanobacteria
(provides food)
Form a thallus (body)
Foliose
Fruticose
Crustose
LICHEN STRUCTURE
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LICHENS AS BIOMONITORS
Thalli
act like sponges
Some species more sensitive than
others to pollutants
Which species are present can
indicate air quality
Most resistant species can also be
analyzed for pollutants
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