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1. Bacteria and their energy
• Autotrophs
• Chemotrophs
• Heterotrophs

2. Autotrophs
• Make their own energy
• Using Solar energy
• Eg. Cyanobacteria

3. Chemotrophs
• Make own Energy
• Using Chemical energy
• Eg. Archaebacteria

4. Bacteria Respiration
• Live without Oxygen
• Obligate Anaerobes • Can live with or
• Facultative without oxygen
Anaerobes • Cannot live without
oxygen.
• Obligate Aerobes

5. Bacteria Reproduction
• Binary Fission
• Conjugation
• Spore Formation

6. Replication
• Binary fission
– one cell splits into two
cells, see diagram
• offspring are genetically
identical to parent

7. Bacterial conjugation
– a form of sexual
reproduction where
bacteria exchange
genetic information
before dividing
• offspring have new
genes (and new
traits)
Figure 1. Schematic drawing of bacterial conjugation. 1- Donor
cell produces pilus; 2- Pilus attaches to recipient cell, brings the
two cells together; 3- The mobile plasmid is nicked and a single
strand of DNA is then transferred to the recipent cell; 4- Both
cells recircularize their plasmids, synthesize second strands, and
reproduce pili. Both cells are now viable donors.

8. Spore Formation: Endospore
• A type of dormant cell
• Exhibit no signs of life
• Highly resistant to
environmental stresses such
as:
-High temperatures
-Irradiation
-Strong acids
-Disinfectants
• Endospores are formed by
vegetative cells in response
to environmental signals that
indicate a limiting factor for
vegetative growth, such as
exhaustion of an essential
nutrient.