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Laura Vallentyne 10/02/07 Microbiology (Bacteria, Viruses, Protistans, and Fungi) 1) Kingdom Monera a) Bacteria i) All prokaryotic and unicellular ii) Most abundant and widespread organisms iii) Many pathogenic iv) Many beneficial v) Size (1) Smallest of all living organisms (2) 0.2- 10 micrometers (3) A single E-coli is about the size of a mitochondria vi) Shapes (1) Coccus (a) sphere shaped bacteria – like anabaena (b) Singles, groups or chains (2) Bacillus (a) Rod shaped (b) May come as singles, pairs or chains (3) Spirillum (a) Spiral shaped cell (b) Like worms, twisted or irregular shape (c) Singles only vii) Importance of Bacteria (1) Pathogenic bacteria (a) Disease causing (2) Cyanobacteria (a) Photosynthetic (b) Rapid growth and proliferation added most of oxygen to the air (3) Nitrogen-fixing bacteria (a) Bacteria live in conjunction with plant roots (b) Convert nitrogen gas into nitrogen that plant can use (c) Natural fertilizer (4) Saprophytic Bacteria (a) Decomposers (b) Release the nutrients in organic material (5) Fermenting Bacteria (a) Yogurt, sauerkraut, cheese (b) Lactobacillus 2) Viruses a) Noncelluar obligate parasites i) Anything that extracts some resource from a host that leads to the detriment of the host ii) Must be a parasite to survive iii) Not cellular – not living violates cell theory b) Extremely small (18-350 Nanometers) c) Consists of: Laura Vallentyne 10/02/07 i) Strand of nucleic acid (1) DNA or RNA ii) Outer Protein coat (1) Surrounds the nucleic acid d) Replicates inside a host cell i) Pirates the host’s metabolic mechanisms (1) Virus lands on cell (2) Adheres to cells (3) Injects nucleic acid (4) DNA gets incorporated in to hosts DNA (5) Host cell replicates, and assembles copies of viruses (6) Cell bursts and releases more viruses e) Hosts immune system fights off the viruses i) Antibodies attach to protein coats and inactivates virus 3) Kingdom Protista a) Unicellular eukaryotic organisms b) Some simple multi-cellular organisms c) Many pathogenic d) Many free-living e) Many closely related to other kingdoms i) Fungus like – plant like – animal like ii) Fungus-like Protistans (1) Saprophytic or parasitic heterotroph (a) Water and slime molds iii) Animal-like protistans (1) Protozoans (“first animals”) (a) Unicellular (b) Heterotrophic (2) Examples of Animal-like protistans (a) Amoeba (i) Locomotion by pseudopodia (“False foot”) (ii) Used to crawl or slowly swim through substance (iii)Some free-living (iv) Some parasitic 1. Amoebic dysentery – water in Mexico (b) Flagellates (i) Locomotion by flagella (ii) Some free-living (iii)Many parasitic 1. Giardia – fecal contamination of pack animals (c) Intracellular parasites (i) Live part of life inside cells of host (ii) Malaria (iii)Transmitted by Anopheles mosquito (iv) Infects human liver and red blood cells (d) Ciliates Laura Vallentyne 10/02/07 (i) Locomotion by cilia – the short hair like (ii) Most free-living (iii)Few parasitic 1. Balantidium coli iv) Plant-like protistans (1) Algae (2) Photosynthetic autotrophs (most) (3) Free-living (4) Unicellular or multi-cellular (5) Examples (a) Diatoms (i) Unicellular (ii) Silica shells (iii)Fresh water and marine water (iv) Mined for abrasives and filters (b) Dinoflagellates (i) Unicellular (ii) Flagella for locomotion (iii)Marine or brackish (iv) Produce neurotoxin (v) Causes red tide when conditions are right (c) Red Algae (i) Multi-cellular (most) 1. Very Plant like (ii) Marine (most) (iii)Uses: 1. Agar – thickening agent 2. Nori the seaweed (sushi) (d) Brown Algae (i) Multi-celluar 1. Marine (most) (ii) E.g. Giant Kelp (iii)Uses: 1. Extracts used in ice cream, beer, etc. (e) Green Algae (i) Unicellular, colonial, or multi-cellular (ii) Mostly fresh water and stagnant (iii)Closest relatives of plants 4) Kingdom Fungi a) Molds, Mushrooms, yeasts b) Most multi-cellular eukaryotes c) Few unicellular (yeasts) d) All heterotrophic i) Most Saprophytic ii) Few pathogenic e) Composed of mycelium (hyphae) Laura Vallentyne 10/02/07 i) Fuzzy strands of cells end to end f) Importance of Fungi i) Diseases (1) Ring worm – athletes foot – yeast infections – valley fever (2) Decomposition (3) Fermentation products (a) Ethanol is produced by yeast (a fungus) (b) Cheeses – blue cheese Roquefort (4) Antibiotics (5) Food (Mushroom)
"Microbiology _Bacteria_ Viruses_ Protistans_ and Fungi_"