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Published byEarl Jones Modified over 9 years ago
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Prokaryotes & Viruses
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Taxonomy Domain Eukarya KingdomAnimalia PhylumChordata ClassMammalia OrderCetacea FamilyDelphinidae GenusTursiops Speciestruncatus Bottlenose dolphin
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Domains Eubacteria (Bacteria) Archaebacteria (Archaea) Eukarya Kingdom Protista Kingdom Fungi Kingdom Plantae Kingdom Animalia
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Prokaryotes vs. Eukaryotes Prokaryotes—simplest, most “primitive” bacteria Eukaryotes— “true” cells, more “advanced” Complex organisms, multicelled
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Prokaryotes No membrane around nucleus No true organelles Single chromosome (nucleoid) May have plasmids Cell wall (most) Reproduce by prokaryotic fission
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Bacterial Shapes Coccus (cocci)—spherical Bacillus (bacilli)—rod Sprillum (spirilla)—spiral, twist
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Bacterial Structures Cell wall Peptidoglycan (polysaccharide) Maintain shape ID species Gram-positive—thick wall Stain purple Gram-negative—thin wall Stain pink
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Bacterial Structures Glycocalyx—capsule or slime layer Attach to structures (teeth, intestine, rocks, etc.) Protection Pili—thin, hair-like proteins Adhere to surfaces Adhere to other baceria Flagellum Movement
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Metabolism Photoautotroph Energy from sun (photosynthesis) Carbon from CO 2 Chemoautotroph Energy from simple compounds (iron, sulfur, etc.) Carbon from CO 2 Photoheterotroph Energy from sun Carbon from organic compounds Chemoheterotroph (most common kind) Energy from simple compounds Carbon from organic compounds
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Prokaryotic Fission Similar to mitosis, but simpler DNA duplicates DNA molecules move to opposite sides of cell New cell membrane & wall form across middle Cell divides
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Conjugation Transfer section of DNA from one cell to another Transfers genes, characteristics Antibiotic resistance
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Domain Eubacteria Cyanobacteria One of most primitive kind Photoautotrophs Produce oxygen “Fix” nitrogen (convert N 2 gas to nitrogen compounds)
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Domain Eubacteria Proteobacteria All gram-negative Chemoautotrophs Important to nutrient cycles Rhizobium Roots of legumes (peas, soybeans, etc.)
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Domain Eubacteria Chlamydia Intracellular parasites One species causes STD Spirochaetes Free-living, parasites, or symbionts Motile “springs” Borrelia burgdorferi—Lyme disease
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Domain Eubacteria Gram-positives Still being sorted out Chemoheterotrophs (most) Lactobacillus—dairy foods (i.e. yogurt) Bacillus anthracis—anthrax Clostridium tetani—tetanus
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Domain Archaebacteria “Extremophiles” Primitive, but resemble other bacteria Different cells walls (no peptidoglycan)
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Domain Archaebacteria Thermophiles Heat lovers Sulfur used to make ATP Temperatures can exceed 110 o C
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Domain Archaebacteria Methanogens Create methane gas Marshes, Antarctica, deep ocean Symbionts (termites, cattle) Important to carbon cycling Anaerobes
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Domain Archaebacteria Halophiles Salt lovers Environments 10x salinity of sea water Dead Sea, Great Salt Lake
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Living things must…. Acquire energy Metabolize Maintain homeostasis Grow Reproduce Respond Adapt
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Viruses Noncellular Infectious parasite Two main characteristics Protein coat around nucleic acid (DNA or RNA) Cannot reproduce itself
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Viruses Herpes Smallpox Hepatitis B Rhino virus (common cold) HIV Influenza Rabies
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Viral Multiplication Attachment Penetration Replication & synthesis Assembly Release
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Viral Multiplication Lytic Pathway—host cell bursts (lysis) & dies, releasing viruses Very rapid
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Viral Multiplication Lysogenic Pathway—host cell lives, viral DNA merges w/ host’s & is duplicated w/ host DNA
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Latent Period virus in lysogenic pathway, reproducing but not showing disease Stress or other stimulus signals virus into lytic pathway Herpes virus Viral Multiplication
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