1. Bacteria
Chapter 18
Biology 1

2. Bacteria Cell

3. Prokaryotes Cells that do not have a nucleus
Exist almost every where on earth
Grow in numbers so great you can see them with the unaided eye
Are placed in either the Eubacteria or the Archebacteria Kingdoms
Make up the smaller of the two kingdoms

4. Eubacteria Make up the larger of the two prokaryote kingdoms
Generally are surrounded by a cell wall composed of complex carbohydrates called peptidoglycan.

5. Cyanobacteria Photosynthetic bacterium Bluish-greenish color
Contain membranes that carry out the process of photosynthesis
Do not contain the same type of chloroplasts as plants do
This bluish-greenish algae can be found nearly everywhere on earth.
Can survive in extremely hot environments and even extremely cold environment

6. Archaebacteria Lack peptidoglycan in cell walls
Have different lipids in their cell membrane
Different types of ribosomes
Very different gene sequences
Archaebacteria can live in extremely harsh environments
They do not require oxygen and can live in extremely salty environments as well as extremely hot environments.

7. Identifying Prokaryotes
Cell Shape
Cell Wall
Movement

8. Bacterium Shapes Cocci~ Sphere shaped bacteria
Bacillus~ Rod shaped bacteria
Spirrillium ~ Spiral shaped bacteria
Flagella~ Leg-like structures that help to propel the bacterium.

9. Gram + and Gram – Bacterium Cell Walls

10. Cellular Walls
Chemical nature of a cell wall can be determined by Gram Staining
By finding out what color the cell produces when it is gram stained you can figure out the type of carbohydrates in the cell wall

11. Movement
Flagella ~ Tail like structure the whips around to propel the bacterium
Cillia ~ Miniature flagella surround the cell that help to “swim”
Non motile ~ Sticky cillia like structures that keep the bacterium from moving

12. Flagella

14. Bacteria and their energy
Autotrophs
Chemotrophs
Heterotrophs

15. Autotrophs
Make their own energy
Using Solar energy
Eg. Cyanobacteria

16. Chemotrophs
Make own Energy
Using Chemical energy
Eg. Archaebacteria

17. Heterotrophs
Obtain food
By eating
Eg. E-coli

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

19. Bacteria Reproduction
Binary Fission
Conjugation
Spore Formation

20. Cellular organism copies it’s genetic information then splits into two identical daughter cells

21. Conjugation A type of bacteria sexual reproduction.
Two organism swap genetic information, that contains the information such as a resistance to penicillin
Can also exchange DNA through a small tube called a pilus (pili is the plural form).

22. 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.

23. Symbiosis
Close relationship between to species in which at least one species benefits from the other
Live together for LIFE

24. Parasitism Bacteria exploit the host cell, injuring them
Eg. Mychobacterium tuberculosis

25. Mutualism
Symbiosis in which two of the species live together in such a way that both benefit from the relationship
Eg. E-coli

26. Nitrogen Fixations
Process by which nitrogen in the atmosphere is converted into a form that can be used by living things

27. THE END

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