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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
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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+the+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-other-coupons.html http://www.myhomecooking.net/bread-recipes/wheat-bread-recipe.htm http://www.bigoven.com/glossary/Blue%20Cheese
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 hyphae(sing. hypha) • Each hypha contains many nuclei and has cell wall containing chitin • Tubes may be separated by cell wall called septa http://sites.google.com/site/rccbiology/home/chapter-21-fungi 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_rprVa-RY4&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-foot-for-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=CCOQ0VU24xw