Is one color and vegetative cell is a different color

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is one color and vegetative cell is a different color flagella staining mordant applied to increase thickness of flagella
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Methods of obtaining pure cultures To obtain pure cultures you need to have two things A Pure Culture Medium
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Pure Culture Contains a single species of microbe Obtained by isolating the progeny of a single cell Initially serious dilutions were used to isolate single cultures Robert Koch’s techniques became the established method to generate pure cultures
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Streak Plate Method Became the accepted way to make pure cultures Initially developed by Koch, its method relied on spreading bacteria from a loop onto agar medium in a series of streaks The loop is flamed & used to generate streaks, subsequently flamed and used again to spread the bacteria further
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Culture Media Media Types: Laboratory media is synthetic media (opposed to natural media) Synthetic media comes in two forms: Defined Synthetic: defined & known quantities of specific nutrients (used on fastidious organisms) Complex media: non-defined, varies slightly from batch to batch. Mostly composed of peptone, beef extract & NaCl and vitamins Nutrient broth and agar medium are both complex media
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Commonly used media peptones protein hydrolysates prepared by partial digestion of various protein sources extracts aqueous extracts, usually of beef or yeast agar sulfated polysaccharide used to solidify liquid media
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Special Purpose Media Used to Isolate & identify particular organism Selective medium: encourages the growth of some organisms but suppresses the growth of others (AB’s) e.g., SPS agar selects for growth of Clostridium botulism Differential medium: has constituents that cause observable changes (pH) where microbiologist distinguish one colony from another e.g., Blood agar (hemolytic)
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Enrichment medium: Allows organisms that normally are not present to grow (not in sufficient numbers). Unlike selective medium enrichment medium does NOT suppress other colonies. Special Purpose Media Blood Agar plate ( used also on fastidious )
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Selective vs Differential Selective and Differential can be us found in one medium Charcoal selective media (CSM) for isolation of Campylobacter
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Bacterial Colony Morphology
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Factor affecting Bacterial
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  • Fall '11
  • EduardoAreche
  • Microbiology, Bacteria, Growth medium, Agar plate, pure cultures, Special Purpose Media

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