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Published byAnabel Griffith Modified over 9 years ago
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Old Kingdom: MONERANS New: Eubacteria & Archaebacteria Bacteria
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Monerans - prokaryotic cells Do not have a membrane-bound nucleus Size is 1-10 micrometers (1 micrometer is 1 thousandth of a millimeter) 4 Phyla (old system) 1. Eubacteria - true bacteria, surrounded by cell wall 2. Archaebacteria - live in harsh environments 3. Cyanobacteria - blue-green, photosynthetic 4. Prochlorobacteria - contain chlorophyll, like plants
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Identification 1. Cell shapes Bacilli - rod shaped
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Cell shape Cocci - spherical
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Cell shape Spirilli - spiral shaped
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Identification 2. Cell wall - Gram staining Gram positive - takes in dye and is violet Gram negative - appears red. Usually disease causing bacteria. Chemical differences in cell wall
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Identification 3. Movement –Flagella –Lash, snake or spiral forward –Glide along slime layer –No movement at all
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Identification 4. Obtain energy Autotrophs - can make own food a. Phototrophic - traps sunlight b. Chemotrophic - uses inorganic molecules
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Identification Heterotroph - cannot make own food. Takes in organic molecules, breaks down and absorbs.
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Respiration Obligate aerobes - must have oxygen Obligate anaerobes - does not need oxygen –Tetanus and Clostridium botulinium Facultative anaerobes - with or without oxygen
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Reproduction Binary fission - asexual cell division Conjugation - sexual exchange of genetic info Spore formation endospore- thick internal wall that encloses DNA. Grows when conditions are right.
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Importance of Bacteria A. Good Bacteria Production of food cheese, buttermilk, wine Industrial use - digest oil from spills, remove poisons from water, used to synthesize drugs.
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Symbiosis - live with other organisms. Ex:E. coli in intestines helps absorption Nutrient flow - bacteria recycle & decompose dead material to return to soil Nitrogen fixation for plants
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Importance of Bacteria B. Bad bacteria Pathogenic - disease causing –Diphtheria, tuberculosis, typhoid fever, tetanus, syphilis, cholera & bubonic plague
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Controlling bacteria growth Freezing - stops growth Refrigeration - slows growth Canning - heat to boil, seals out air but some endospores will survive
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Controlling bacteria growth Drying - no moisture Salt - if enough then no growth Radiation & alcohol - used to sterilize & kill Antibiotics - drugs & natural compounds that attack and destroy
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Viruses A noncellular particle made up of genetic material and protein that can invade living cells (a parasite needs a host)
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Viruses A. Composed of DNA or RNA (not both!) surrounded by a capsid (protein coat) B. Not composed of cells. Infect living cells, grows, reproduces & evolves –Bacteriophage: virus that invades bacteria C. Shapes –Rod –Tadpole –Many sided (helical or cube-like)
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Viruses D. Vary in size (20 - 400 nanometers) 1 nanometer = 1 billionth of a meter E. Viruses classifed according to host –Bacteria –Plant viruses –Human & other animal viruses (HIV & SIV) F. Viruses mutate and become stronger in next generation
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Lytic Virus invade or infect a living host to reproduce (kills host) A. Infection/attachment - injects DNA into host cell B. Growth - virus DNA shuts down normal cell activities to make copy of itself C. Replication = uses materials of host to make copies D. Cell lysis = infected cell bursts & releases new viral particles that will infect other cells
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Lysogenic Infection Does not lyse the host cell, it justs incorporates itself in host DNA (prophage) Ex: Retrovirus - contains RNA. When in host cell, the genetic info is read backwards (RNA to DNA). Some cause cancer. HIV is a retrovirus
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Viral Diseases Chicken pox Cold sores Yellow fever Measles Common cold HIV Some forms of cancer (HPV)
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Famous People Jonas Salk - polio vaccine Louis Pasteur - rabies vaccine Edward Jenner - small pox vaccine
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Draw picture of virus and label (DNA or RNA)
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Copy and label picture of a bacteria from overhead.
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The End
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