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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- copyright Franciscop2 2008]]
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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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| − | *'''Gram-positive bacteria''': cell wall consists of peptidoglycan layer, with teichoic polymers attached, e.g. ''Staphylococcus''
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| − | *'''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]]
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| − | [[Image:497px-Arrangement of cocci bacteria svg.png|thumb|right|100px|Arrangement of cocci bacteria]]
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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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| − | *'''Cocci'''- round shape, e.g. Streptococci, Staphylococci, Neisseria
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| − | *'''Rods''' or '''bacilli'''- long shape, e.g. Coliforms, Bacillus, Spirochaetes[[Category:Bacteria]]
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