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9 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Classification by shape |
Bacillus rod shapes Cocci spherical Spirillum corkscrew |
B C S |
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Gram stain classification |
Gram positive or negative bacteria Due to cell way ( polysaccharides and polypeptides-peptidoglycanPrevents osmotic lysis and polypeptides-peptidoglycan Prevents osmotic lysis |
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Gran negative |
More complex cell walls Peptidoglycan is supplemented by lipoplysaccharides Dont retain crystal violet Appear red Not affected by antibacterial enzyme lysozyme e.g.penicillin |
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Gram positive |
Lack lipopolysaccharide Retain crystal violet Appear purple More susceptible to antibiotics |
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Conditions necessary for growth |
Bacteria can divide once ever 20 minutes in optimum conditions Conditions vary between bacteria |
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Micro organisms requirements (nutrients) |
Nutrients - supplied by agar in labs Contain carbon( glucose) nitrogen in organic and non oganic, vitamind and mineral salts |
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Micro organism requirements ( temperature) |
Growth is normally regulated by enzymes 25-45°c is favoured by most bacteria Optimum for mammal pathogens is 37°c |
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Microorganism requirements ( pH) |
Most prefer slightly alkaline conditions (7.4) Fungi grow better in slightly acidic |
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Micro organism requirements (oxygen) |
Oxygen is required for metabolic processes in obligate aerobes and facultative anaerobes Obligate anaerobes cant grow in its presence e.g. clostridium causes gangrene in wounds |
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