All Bacteria have the following characteristics:
- Unicellular and stick together in colonies
- Are prokaryotic (no nucleus, vacuoles, mitochondria or chloroplasts)
- They have a single chromosome in a DNA loop
- They reproduce asexually by binary fission
- Live in moist environment and are inactive in dry environments
Two groups of Bacteria
1. Archaebacteria – primitive bacteria that live in harsh environments
2. Eubacteria – most common bacteria eg: E. Coli
Other ways of classifying bacteria are:
3. Aerobic or anaerobic
4. Autotroph or heterotroph
Bacteria Reproduction:
BINARY FISSION
– similar to mitosis (simple cell division)
STEPS:
- DNA replicates (doubles)
- a cross wall forms dividing the cell into two identical bacteria
Some bacteria (eg: E.Coli and Salmonella) reproduce by conjugation (sexual reproduction)
