Transcript 3.1 Fungi - MsNAhmad

Diversity of Living Things
3.1: Fungi
Plants & Fungi
• Fungi have many similarities to plants, but the
differences distinguish fungi as a separate
kingdom
• Similarities with plants:
– eukaryotic cells with organelles and cell walls
– most do not move and grow in soil or other surface
– reproduction sexual, asexual, or both
Fungi & Plants
• Differences from plants:
– can have many nuclei in cells (plants only one
nucleus per cell)
– are heterotrophs (plants are mostly
autotrophs)
– have few storage molecules (plants have
starch to store carbohydrates)
Fungi & Plants
• Differences from plants (cont’d):
– have no roots (plants have roots)
– have chitin in cell walls (plants have cellulose
in cell walls)
– do not reproduce by seed (some plants
reproduce by seed)
Importance of fungi
• Major decomposer: cycling of nutrients
• Symbiotic relationships with plants: fungi help
plants attain nutrients from soil, plants give
fungi food from photosynthesis
http://www.livescience.com/php/multimedia/imagedisplay/img_display.php?pic=060410_ground_fungi_02.jpg&cap=Fungi+decomposing+a+fallen+log+in+th
e+Amazonian+rainforest+of+Peru.+Credit%3A+Steven+Allison
Importance of fungi cont’d
• Cause diseases in animals and plants
• Source of consumer products: mushrooms,
truffles; help to make bread, soy sauce, blue
cheese and alcohol; source of antibiotic
penicillin; used in genetic engineering
http://qtips4you.blogspot.com/2010/10
/bogo-kikkoman-and-othercoupons.html
http://www.bigoven.com/glossary/Blue%
20Cheese
http://www.myhomecooking.net/breadrecipes/wheat-bread-recipe.htm
Classification and Phylogeny
• More than 100 000 species of
fungi have been identified
• There are 5 major phyla
including Basidiomycota
(mushrooms) and
Zygomycota (moulds on food)
• Phyla range in size from
microscopic to largest on
Earth (Armillaria ostoyae) is
2, 384 acres long which is
equivalent to 1, 665 football
fields!)
• See Table 1 on p. 81
http://thedarksideoftheshroom.blogspot.com/2010_04_01_archive
.html
Characteristics
• Display extreme diversity in
terms of life cycle and
characteristics
• Body of fungi is composed
of network of branching
filaments called mycelium.
The filaments are called a http://sites.google.com/site/rccbiology/home/chapter-21-fungi
hyphae (sing. hypha)
• Each hypha contains many
nuclei and has cell wall
containing chitin
• Tubes may be separated by
cell wall called septa
http://www.fungionline.org.uk/3hyphae/1hypha_ultra.html
Characteristics cont’d
• Most fungi are
multicelluar but some
can be unicellular. Yeast
is a unicellular fungi
which is involved in
bread and alcohol
production
• All fungi are
heterotrophs
(saprophytes or
parasites)
http://www.pmbio.icbm.de/mikrobiologischer-garten/eng/enhef01.htm
Video clip on Fungi
• http://www.youtube.com/watch?v=5_rprVaRY4&feature=fvwrel
Characteristics cont’d
• Fungi use external digestion (digest then
ingest)
– They grow next to or within food source and
release enzymes which break down food so that
nutrients can be absorbed across hypha
– Distribution of absorbed nutrients occurs through
the mycelium
– Most fungi store their food as glycogen (like
animals)
Symbiotic Relationships in Ecosystems
• Lichens are symbiotic combinations of sac
fungi and cyanobacteria or green algae
– Fungi supply materials for photosynthesis and
plants return favour by providing food to fungi
http://www.sheridanmedia.com/news/community-colleges-quotpartnershipsquot-and-lichens13308
Other symbiotic relationships
• Many examples between animals and fungi
– Leaf-cutter ants and fungi
http://ecolibrary.org/page/DP176
Mycorrhizae
• Mycorrhizae involves more than 80% of all
plants
– Hyphae grow around plant’s root cells. Fungi give
plant nutrients like phosphorous and plant
provides fungi with food
http://www.apsnet.org/edcenter/illglossary/Pages/I-M.aspx
Decomposers and disease
• Fungal diseases are called mycoses
• Some diseases caused by fungi are mild like
athlete’s foot and ringworm infection
• Some cause respiratory diseases such as
Aspergillosis in humans like Blastomycosis and
Cryptococcosis
http://littletvaddict.com/2010/05/otc-treatment-for-atheletes-footfor-someone-on-warfarin/
http://health.allrefer.com/health/cryptococcosis-cryptococcosis-on-the-forehead.html
Video of disease-causing fungi:
Cordyceps
• http://www.youtube.com/watch?v=CCOQ0VU
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