Upload
violet-webb
View
215
Download
0
Embed Size (px)
Citation preview
1
Fungi
2
Introduction
• High points - fermented beverages, leaven bread
• Low points - athletes foot, jock itch, that pink stuff that grows on your shower curtain
3
Shared Characteristics• Distinctive fungal features
– Fungi are heterotrophs.– Fungi have several cell types.– Fungi have cell walls that include chitin.
4
The Body of a Fungus• Fungi exist mainly in the
form of slender filaments (hyphae).
5
The Body of a Fungus
• Fungi cell walls are formed of polysaccharides and chitin.
– not cellulose like those of plants
6
How Fungi Reproduce
• Fungi are capable of both sexual and asexual reproduction.
– Fungi reproduce sexually after two hyphae of opposite mating type fuse.
7
How Fungi Reproduce
• Spores most common means of reproduction
– may form from asexual or sexual processes
– most often dispersed by wind but some spread by insects or other small animals
http://www.youtube.com/watch?v=qDwgSWDqKoQ
8
How Fungi Obtain Nutrients
• All fungi obtain food by secreting digestive enzymes and then absorbing the organic molecules produced (external digestion).
– extensive hyphae network provides enormous surface area for absorption
9
Four Major Groups of Fungi
• Five groups– Chytridiomycota– Zygomycota– Basidiomycota– Ascomycota– Deuteromycota
Means “second-
fungi. Actually an
Artificial grouping “Imperfect” fungi-penicillin, athlete’s foot
10
Chytridiomycota
• aquatic, flagellated fungi (only fungus to have flagella)
11
Zygomycota
• includes common bread molds• Life cycle includes a zygospore (contains
zygotes formed during sexual phase of mold’s life cycle)
12
Basidiomycota (club fungi)
• Most familiar fungi (mushrooms, toadstools, puffballs, rusts, and smuts)
• Basidia are found on the underside of the mushroom cap
13
Ascomycota (Sac Fungi)
• Very large group including yeasts and cup fungi
• Named for the ascus, reproductive structure that contains spores
• Life cycle includes both sexual and asexual reproduction-during asexual reproduction the spores are called conidia
14
Ecology of Fungi
• Fungi and bacteria are the principal decomposers in the biosphere.
• Fungi often act as disease-causing organisms for both plants and animals.
– agricultural damage– human health
15
Ecology of Fungi
• Mutualistic associations– lichens - fungi and green algae/ plants– mycorrhizae - fungi and plant roots
16
Lichens
• Lichens are symbiotic associations between a fungus and a photosynthetic partner.
17
Mycorrhizae
• Roots of about 90% of all kinds of vascular plants are involved in mutualistic symbiotic relationships (mycorrhizae).
18
Mutualistic Animal Symbioses
• A range of mutualistic fungal-animal symbioses has been identified.
– Ruminants – fungi in gut – release enzymes
– leaf-cutter ants – fungal gardens
19
Fungal Parasites and Pathogens
•http://dermatology.fromyourdoctor.com/pennsylvania/northern_cambria/ncmcascp/health/topic.do%3Bjsessionid=91424179D20C68170267C22C5B891CF7?title=Fungal+Skin+Infections+tinea+ringworm&t=2199
•http://www.nature.com/eye/journal/v17/n8/fig_tab/6700557f2.html
20
Fungi in History- Ergot Poisoning
The Salem Witch Trials• Toxicologists now know that eating ergot-contaminated
food can lead to a convulsive disorder characterized by violent muscle spasms, vomiting, delusions, hallucinations, crawling sensations on the skin, and a host of other symptoms — all of which, are present in the records of the
Salem witchcraft trials
http://www.wtps.org/wths/imc/Teacher_Assignment/english/Thomas%20the%20salem%20witchtrials.htm
21http://www.flickr.com/photos/gdraskoy/1096292603/
22
References
• Information• Miller, . (2005). Biology. Upper Sadle River, NJ: Prentice Hall. • Star, , & Taggert, . (2004). The Unity and diversity of life. US: Thomson.
• Images• http://www.bbc.co.uk/oxford/pictures/visions_science/pop_up_01.shtml• http://chicagoist.com/2006/05/24/beer_hall_homes.php• http://localcrank.wordpress.com/2009/07/07/today-in-history-15/• http://www.rayoverde.org/• http://researchstories.asu.edu/2007/10/the_art_of_life.html• http://faculty.southwest.tn.edu/rburkett/classification_of_organisms.htm• http://www.nmnh.si.edu/rtp/students/2007/
schedule07_entomology_tour_photo1.html