Transcript Ch19 Bacteria

Monerans:
Bacteria
Friend or Foe
Prokaryotes
Bacteria = Prokaryotes
 Discovered when Robert Hooke and Anton
van Leeuwenhoek invented the microscope
 Bacteria are the smallest living organism
 Unicellular and lack nucleus
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Classifying Prokaryotes
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2 Different Groups:
– Eubacteria
 Great variety
 Live almost anywhere (land, water, & in humans)
 Cell wall contains peptidoglycan (carbohydrate)
– Archaebacteria
 Chemically different because lack peptidoglycan
 DNA more like that of eukaryotes
 Live in harsh environments (no oxygen, very salty, &
high temperatures)
Identifying Prokaryotes
Identified by Shape, Chemicals in Cell
Walls, Way they Move, & Obtaining
Energy
 Shapes:
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– Bacilli = Rod Shaped
– Cocci = Spherical Shaped
– Spirilla = Spiral & Cork-screw
Obtaining Energy
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Heterotrophs
– Chemoheterotrophs = take in organic molecules
– Photoheterotrophs = photosynthetic (use
sunlight) & need organic molecules for energy
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Autotrophs
– Chemoautotrophs = make organic molecules
from carbon dioxide
– Photoautotrophs = use light energy and water to
carbon compounds and oxygen (like plants)
Living Conditions
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Obligate Aerobes = need oxygen to live
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Obligate Anaerobes = needs no oxygen
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Falcultative Anaerobes = can live with or
without oxygen
Reproduction
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Binary fission = cell grows to double its
size, DNA copied, and then splits
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Conjugation = DNA exchanged by bridge
that forms and passes on genes
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Endospores = spores formed when in bad
conditions to live. Spores are dormant, then
awaken when good conditions
Bad Bacteria
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Pathogens = disease causing (i.e. E. coli )
Good Bacteria
Vaccines = preparation of weak pathogen
 Antibiotics = block the regrowth and
reproduction of pathogens
 Decomposers = help the ecosystem
recycle nutrients
 Human Uses:
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– Clean oil spills because some digest petroleum
– Purifying water by removing waste products
– Making vitamins
– Foods & Drinks to help Human Body digestion
Bacteria Shakes!!!!
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Probiotic Kefir Milk
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L. casei
L. acidophiles
L. plantarum
L. rhamnosus
S. diacetylactis
S. florentinus
B. bacterium longum
Leuconostoc cremoris
B. bacterium breve
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Lowfat Milk
Ice Cream
Whey Protein
Strawberries
Ice