- Cellular organisms.
- Most are unicellular.
- The smallest living cell.
- Bacteria range from 0.5 un to 5.0 micrometers in length.
- Smallest bacteria Bruvendomonas duminata 0.33 micrometers.
- Prokaryotes family
- Most bacteria have a cell wall that surrounds the plasma membrane.
- Cell wall and cytoskeleton is an important way to classify bacteria.
·
Three common shapes
(CBS)
1.
Cocci
2.
Bacilli
3.
Spirilla ( Vibro colli)
- Bacteria can reproduced by
- Binary fission (one cell divides into two similar cells)
- Budding
- Fragmentation ( one cell divides to several Cell).
- Most bacteria that are motile move by their flagella.· Some bacteria called gens name only – Ex : Salmonella, Pseudomonas· Some bacteria called specific species name only – Ex : E.coli.
Gram Positive
|
Gram Negative
|
1.
Outer membrane is absent.
2.
Cell wall
is 20-30 nm thick.
3.
Thick peptide glycan (murein).
4.
The wall contains 70-80% peptide glycan (murein).
5.
Cell wall contains teichoic acid.
6.
A few pathogenic bacteria belong to Gram positive group.
7.
Basal body of flagellum contains two rings.
|
1.
Thick Lipo poly saccharide (Endotoxin).
2.
Cell wall
is 8-12 nm thick.
3.
Thin Peptido glycan (murein).
4.
The wall contains 10-20% peptide glycan (murein).
5. teichoic acid are absent.
6.
Most of
the pathogenic bacteria belong to Gram negative group.
7.
Basal body of flagellum contains four rings.
|
