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