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− | '''Bacterial genome''':
| + | #REDIRECT [[Bacterial Cell Structure]] |
− | *Contains double-stranded DNA
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− | *Prokaryotic DNA differs to eukaryotic DNA:
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− | **Few repeated sequences
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− | **Most of the DNA is transcribed
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− | **No intervening sequences within structural genes
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− | '''Cytoplasm''':
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− | *Does not contain mitochondria, lysosomes or Golgi bodies (found in eukaryotic cells)
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− | *Contains mesosomes- thought to be primitive endoplasmic reticulum
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− | '''Surface components''':[[Image:478px-Bacteria cell wall svg- franciscosp2.png|thumb|right|100px|'''Structure of cell wall''' Franciscop2 2008, WikiMedia Commons]]
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− | *Fimbriae- also known as pili, these are hair-like structures that allow bacteria to adhere to each other
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− | *F-type pili- also known as sex pili, these act as conjugation tubes during sexual reproduction
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− | *Capsules/slime- serve to adhere bacteria to cells and provide protection from phagocytosis and dehydration, e.g. hyaluronic acid
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− | *Flagella- help the bacteria move around
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− | One way bacteria can be classified is by the structure of the cell wall:
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− | *'''[[:Category:Gram positive bacteria|Gram-positive bacteria]]''': cell wall consists of peptidoglycan layer, with teichoic polymers attached, e.g. ''Staphylococcus''
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− | *'''[[:Category:Gram negative bacteria|Gram-negative bacteria]]''':peptidoglycan layer is thinner, but surrounded by outer membrane of lipopolysaccharides and lipoproteins, e.g. salmonella
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− | [[Image:427px-Arrangement of bacilli bacteria svg.png|thumb|right|100px|'''Arrangement of bacilli bacteria''' LadyofHats 2006, WikiMedia Commons]]
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− | [[Image:497px-Arrangement of cocci bacteria svg.png|thumb|right|100px|'''Arrangement of cocci bacteria''' LadyofHats 2006, WikiMedia Commons]]
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− | {| border="1"
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− | |+ Components of bacterial envelope
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− | ! Component !! Gram positive !! Gram negative
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− | |-
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− | ! Peptidoglycan
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− | | Yes || Yes
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− | |-
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− | ! Teichoic acid
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− | |Yes
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− | |No
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− | |-
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− | ! Lipoprotein
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− | |No
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− | |Yes
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− | |-
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− | ! Lipopolysaccharide
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− | |No
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− | |Yes
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− | |-
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− | ! Phospholipid
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− | |No
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− | |Yes
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− | |}
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− | Another method of classification is the shape and arrangement of the bacteria themselves:
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− | *'''[[:Category:Cocci|Cocci]]'''- round shape, e.g. Streptococci, Staphylococci, Neisseria
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− | *'''[[:Category:Rods|Rods]]''' or '''bacilli'''- long shape, e.g. Coliforms, Bacillus, Spirochaetes[[Category:Bacteria]]
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− | [[Category:To_Do_-_Bacteria]]
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