1. EUBACTERIA and ARCHAEBACTERIA pp.360-372

2. Classifying Prokaryotes
All prokaryotes were once placed in the Kingdom Monera.
Recently, biologists divided them into two different kingdoms: the Eubacteria and the Archaebacteria.

3. Eubacteria Archaebacteria
No peptidoglycan in cell walls
Live in extreme environments
Thermophiles, halophiles, methanogens
Peptidoglycan in cell walls
Cannot survive in extreme environments
Bacteria & cyanobacteria
Prokaryotic
No nucleus
Single-celled
Ribosomes
No other organelles

4. Archaebacteria 
DNA shows a closer evolutionary relationship to eukaryotes
Many archaebacteria live in extreme environments.
Methanogens live in oxygen-free environments (ex. thick mud & animal digestive tracts)
Halophiles live in salty environments
Thermophiles live in hot environments (ex. hot springs)

6. 2. Eubacteria
Eubacteria have a cell wall that protects the cell and determines its shape.
Eubacteria include organisms that live in a variety of environments, including:
in fresh and salt water
on land
in the human body

7. E. coli, a Typical Eubacterium
(Peptidoglycan)
A bacterium such as E. coli has the basic structure typical of most prokaryotes: cell wall, cell membrane, and cytoplasm. Some prokaryotes have flagella that they use for movement. The pili are involved in cell-to-cell contact. The cell walls of eubacteria contain peptidoglycan.

8. Types of Eubacteria Bacilli = rod-shaped Cocci = spherical-shaped
Spirilla = spiral & corkscrew-shaped
Prokaryotes can be identified by their shapes. Photo Credit: ©David Scharf/Peter Arnold, Inc.

9. Arrangement or Grouping
Paired = diplo
Filamentous (chains) = strepto
Colonial (grape-like clusters) = staphylo

10. Identifying Prokaryotes:
Two different types of cell walls are found in eubacteria.
A method called gram staining tells them apart.
Gram-positive bacteria have thick cell walls with large amounts of peptidoglycan.
Gram-negative bacteria have thinner cell walls inside an outer lipid layer.
Copyright Pearson Prentice Hall

12. Mobility Some have one or more flagella
Some lash, snake or spiral forward
Some glide on a layer of slime-like material

13. Copyright Pearson Prentice Hall
Nutrition
Prokaryotes are divided into two main groups:
Heterotrophs get their energy by consuming organic molecules made by other organisms.
Include chemotrophic heterotrophs & phototrophic heterotrophs
Autotrophs make their own food from inorganic molecules.
Include chemotrophic autotrophs & phototrophic autotrophs
Copyright Pearson Prentice Hall

14. Copyright Pearson Prentice Hall
Releasing Energy 
released by cellular respiration (aerobic) or fermentation (anaerobic) or both
1. Obligate aerobes require oxygen
2. Obligate anaerobes live without oxygen because they may be killed by it
3. Facultative anaerobes can survive with or without oxygen
Copyright Pearson Prentice Hall