I.
The Kingdom
Fungi
A. The kingdom fungi is one of the four major kingdoms
in the domain eukarya
B. Fungi are more closely related to animals than any
other kingdom
C. Fungi play a vital role in many chemical pathways
fundamental to life on the planet
1. Many plants could not grow at all without their
fungal counterpart
2. Fungi are present in every ecosystem
II.
General biology
and major distinguishing characteristics
A. Fungi are heterotrophs; they cannot manufacture
their own food as photosynthetic organisms can
B. Most species of fungi are saprotrophic; they
decompose dead organic matter
C. Some species are parasites and others are mutualistic
D. Fungi are the principle decomposers in every
ecosystem
1. Fungi live by absorptive nutrition: they secret digestive enzymes that break down
large food molecules in the environment
2. Once the molecules are broken down the products are
than absorbed through the plasma membrane
3. Fungi store their food as glycogen (like
animals), while plants and green algae store their food as starch
E. Most fungi are multicellular, but
single-celled species are found in most of the fungal groups.
1. Unicellular members of all but the
chytrids are called yeast
2. The body of a multicellular fungus is
called a mycelium
3. It is composed of rapidly growing
individual tubular filaments called hyphae
4. Cell walls of hyphae are strengthened by
microscopic fibrils of chitin, a nitrogen-containing polysaccharide (cellulose
is rarely present in the cell wall of fungi)
5. If there are flagella it is usually the posterior
whiplash type and the mitochondria are usually flattened cristae
III.
Major
Evolutionary Groups
A. Fungi are categorized into phyla (divisions) based on the
type of structures produced during sexual reproduction
B. There are thought to be five major classes of
fungi
1. Chytridiomycota
2. Zygomycota
3. Glomeromycota
4. Ascomycota
5. Basidiomycota
C.
There are more
than 70,000 species and they
occupy a variety of habitats over most of the earth (some say there may even be
about 1.5 million species)
IV.
Major
phyla/classes of Fungi
A. Chytridiomycota
1. Evolutionary relationships between chytrids and other
fungi indicate that they are paraphyletic, a subgroup to the remaining fungal
groups
2. There is considerable variation in the morphology and
ecology of chytrids
3. These fungi live mostly in water rather
than soil
4. Regarded as water molds
5. Some are freshwater, some marine; some are parasites
on plants and others live on decaying plants and insect parts
6. They feed on small-celled organisms and debris in
aquatic environments
7. These are the only fungi with gametes
having flagellated cells
8. Allomyces, is a well studied genus of chytrids
9. There are fewer than 1,000 described
species of chytrids
B. Zygomycota
1. This phylum of fungi are also
paraphyletic
2. They are usually saprotrophs but there
are some parasites
3. Hyphae lack septa (internal cross walls);
Septa are found only in the reproductive structures
4. More than 700 species have been found
5. An example of this phylum is Rhizopus, Rhizopus stolonifer black bread mold or Rhizopus microsporus, a rice pathogen
C. Glomeromycota
1. This class is terrestrial only
2. They associate with plant roots and so
are to crucial to the existence of some plant species
3. Half the fungi found in soils are
glomeromycetes
4. Fewer than 200 species have been
described, but 80 to 90 percent of all plants have associations with them
D. Ascomycota
1. A diverse group of fungi found in marine,
freshwater, and terrestrial habitats
2. This group is also known as sac fungi
(ascus means sac)
3. Characterized by perforate septate hyphae
and production of an ascus (sac) following sexual
reproduction
4.
The
asci (pl. of ascus) occur in a mycelium called an ascocarp
and they contain ascospores
5.
There is an estimated 60,000
known species of ascomycota
6. Some examples of fungi in this phylum are most of the colored molds on foods, antibiotic producers such as Penicillium, yeasts, morels, and truffles
7. Yeast are important in leavening bread by
CO2 production and in producing ethanol for alcoholic beverages
8. Lichens are symbiotic associations between Ascomycetes (98%)
and certain green algae or cyanobacteria
9. In this symbiotic relationship the photosynthetic
algae provide the food and the fungus provides shelter
E. Basidiomycota
1. Are often referred to as the club fungi
2. This group includes some serious plant diseases such
as rusts and smuts
3. Some examples of basidiomycetes are mushroom,
puffballs, shelf fungi, birds nest fungi, and stinkhorns
4. Shelf fungi are particularly important in breaking
down wook
5. About 25,00 species of basidiomycetes have been
described
V.
Distribution of
Fungi in the biosphere
A. Fungi have colonized all the major habitats of the
world
1. They occur in marine and freshwater environment
2. High mountains and lowlands
3. Permanently waterlogged swaps and harsh deserts
4. All types of woodlands, coniferous forests, deciduous
woodlands, coniferous forests and plantation
B. In addition to colonizing the aquatic and terrestrial
world fungi have also made there way into animal and human organisms
VII. Diversity
and Adaptations to the Environment
A.
Fungi are able
to tolerate highly hypertonic solutions this adaptation helps some species be
more resistant to bacterial damage
B.
Many fungi
tolerate temperatures as low as -6°C and some tolerate temperatures over 50°C
C.
In 1993 the
different species of fungi worldwide was estimated to be approximately 1.5
million different species, today this is suggested to be too low of an
estimation
VIII.
Economical/Human
Use
A.
Fungi is very
popular in many cultures and countries as food source
1. Mushrooms like button mushrooms, porcini, Portobello,
chanterelle, oyster, shiitake, truffles, and morels to name a few
2. Tofu is a result of soy beans (often times) being
colonized by a filamentous fungi
3. Quorn, a fungal protein is the western version of
tofu that is becoming increasingly popular among vegetarians
B.
Puffball
mushrooms have been used in parts of
C.
Fungi as
dyestuff is very popular today in some countries
1. Seventy different colors can be produced from larger
fungi
2. Wool, silk, hair, and paper call all be dyed in this
way using various species of fungi
D.
Fungi also has a
long history of being used in medicines
1.
Penicillin is
perhaps one of the most widely known medicines derived from fungi
2. Bracket and stomach fungi have been used in medicine
for thousands of years by communities for their antibacterial activity and a
rapid clotting aide
3. In eastern Asia especially
4. There is currently research being conducted to use
fungi as a treatment option among certain cancer patients
IX.
Medicinal
mushroom modulators of molecular targets as cancer therapeutics
A.
This is a
research that was conducted at Biodiversity and
Biotechnology Center of Cryptogamic Plants and Fungi, The Institute of
Evolution,
B.
The main focus
of this research appeared to have been mushrooms
targeting processes such as apoptosis, angiogenesis, metastasis, cell cycle
regulation, and signal transduction cascades
C.
Polysaccharides
or polysaccharide–protein complexes from mushrooms that appear to enhance
innate and cell-mediated immune responses
D.
Exhibit
antitumor activities in animals and humans, and demonstrate the anticancer
properties of selenium compounds accumulated in mushrooms
E.
Immunomodulators
isolated from more than 30 mushroom species have shown anticancer action in
animals, some of these mushrooms have moved on to successful human trials
Works Cited
Amy Y Rossman and Mary
E.Palm,. (2006). Why are Phytophthora and other Oomycota not true Fungi?. Retrieved July 20, 2007, from
APSnet Web site: http://www.apsnet.org/education/IntroPlantPath/PathogenGroups/oomycet es/default.htm
Fungi. Retrieved July 20,
2007, from The Biology Web Clinton Community College Web site: http://faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20102/Bio%20102%20lectures/Fungi/fungi.htm
Introduction to the
Chytridiomycota. Retrieved July 20, 2007, from University of California Museum
of Paleontology Web site: http://www.ucmp.berkeley.edu/fungi/chytrids.html
Sadava, D, Heller, H,
Orians, G, & Purves, W (2006). Eight edition: Life the Science of Biology.
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Walting,
Zaidman, B., Yassin, M., Mahajna,
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