1. Bacteria
Our invisible friends

2. Bacteria
Bacteria are microscopic organisms that are prokaryotes.

3. Bacteria are prokaryotes
Pro – before
Karyon – nucleus
The simplest forms of life are prokaryotes.
Earth’s first cells were prokaryotes.

4. Bacteria Prokaryotes are divided into two domains: 1. Eubacteria
2. Archaebacteria

5. Lots of Them! Prokaryotes are Earth’s most abundant life forms.
They can survive in many environments.
They can get energy from many different sources.

6. Prokaryote Review Mostly single-celled No nucleus or organelles
Circular chromosomes
Cell walls
Reproduce mostly asexually
Anaerobic or aerobic
Heterotrophic or autotrophic

7. Eubacteria Very strong cell walls Contain peptidoglycan
Some have a second cell wall

8. Eubacteria Parasitic heterotrophs (Streptococcus) Saprophages
Sapro = death
Phage = eat
Cyanobacteria (blue-green algae)
Photosynthetic
Chemosynthetic autotrophs (Rhizobium)

9. Archaebacteria Methane producers – anaerobic Halophiles Thermophiles
Halo = salt
Philia = love
Thermophiles
Thermo = heat

10. Prokaryote Structure

11. Prokaryote Structure
Prokaryotes are microscopic, unicellular organisms.
They have some characteristics of all cells, such as DNA and ribosomes.
Lack a nuclear membrane and other membrane-bound organelles

12. Bacteria are Named by Shape
Cocci (ball-shaped)
Streptococcus mutans
Bacillus (rod-shaped)
Clostridium botulinum
Spirilli (spiral-shaped)
Treponema palladium

13. Shapes
Cocci
Bacilli
Spirochetes

14. Movement Prokaryotic flagella are made of filaments.
Flagella help prokaryotes to move toward materials that they need to survive.

16. Germ Theory of Disease Joseph Lister – Aseptic Techniques
Robert Koch – Germ Theory
A specific microorganism causes a specific disease