1. Kingdoms Archaebacteria and Kingdom Eubacteria

2. General
Prokaryotes are single-celled organisms. They are the smallest, simplest organisms.

4. Kingdom Archaebacteria
Found in anaerobic (no oxygen) and extreme conditions
high [salt], high temperature, low pH
believed to be the conditions on the early earth
earth’s early atmosphere did not contain oxygen

5. Kingdom Eubacteria includes common bacteria
largest of the two bacteria kingdoms
Bacteria are either gram positive or gram negative
Contain peptidoglycan in cell wall

6. have a cell wall, a cell membrane surrounds the cell but no membrane-bound organelles or nucleus
are covered by a layer of “slime” called a capsule.

7. They exist in three basic shapes:
Cocci – spherical
Bacilli - rod-shaped
Spirilla - spiral

8. Some bacteria are able to move using special cell structures called cilia and flagella.

9. Respiration Obligate aerobes must have oxygen.
Obligate anaerobes cannot survive in the presence of oxygen.
Facultative anaerobes will use oxygen if present but don’t need it.

11. Nutrition Most are heterotrophs Some are autotrophs
They either use chemicals as a source of energy (chemoautotrophs) or are photosynthetic (photoautotrophs).

12. Reproduction
Prokaryotes have a single circular chromosome attached to the inside of the plasma membrane.
Asexual reproduction
splitting in two in a process called binary fission.
The DNA is copied and the cell divides into two identical cells.

13. Sexual reproduction
combines genes from two different bacteria to increase variation.
Three types of sexual reproduction in bacteria:
Conjugation
Transformation
transduction

15. Conjugation
Two cells join briefly and one cell donates some DNA (called a plasmid) to the other one. Sometimes part of the cell’s chromosome is donated as well.

16. Transformation - Bacteria can also pick up pieces of DNA from the environment.
3. Transduction - sometimes viruses transfer pieces of DNA from one cell to another.

18. Bacteria and Disease
Bacteria that cause disease are known as pathogenic bacteria

19. Bacteria cause disease in one of two ways:
Damage cells and tissues by breaking down the cells for food. For example, Mycobacterium tuberculosis destroys lung tissue.

20. Releasing toxins that interfere with the normal functioning of the host. For example, Corynebacterium diphtheriae releases toxins into the bloodstream where they cause breathing difficulty, heart failure, paralysis, and death.

21. Other Diseases Caused by Bacteria:
Tetanus
Botulism
Chlamydia
Leprosy
Necrotising Fasciitis (flesh eating disease)
Salmonella Food Poisening

22. Control of Bacterial Growth
Disinfectants
Kill bacteria on surfaces, floors and non-living objects.
Usually chemicals such as alcohols, bleach, hydrogen peroxide or iodine
Antiseptics
Kill bacteria on the skin of humans or animals
Bactericidal – kill bacteria outright
Bacteriostatic – stop bacteria from growing or dividing but don’t kill them (often antibiotics are bacteriostatics)

23. Natural Body Defenses:
Skin
Fever
White blood cells
Antibodies
Attacks the bacterium
Antitoxins
Attacks or neutralizes the toxin produced by the bacterium

24. Vaccines
small doses of live bacteria, killed bacteria, or parts of bacterial cells which cause an immune response
if exposed to that bacterium again in the future, your immune system will launch a strong response to it.
 Antibiotics
are compounds that interfere with the normal growth of bacteria.

25. Useful Bacteria Decomposers (saprophytes) Nitrogen Fixation
Break down complex organic molecules into simpler substances
Used to our advantage in sewer treatment
Nitrogen Fixation
Take free nitrogen (N2) and “fix” it into a form usable by plants (ex. Ammonia NH4)
form symbiotic relationships with plants
release usable nitrogen compounds to plants

26. Intestinal Bacteria “Clean-Up Teams” Manufacturers
Form symbiotic relationships with animals
Bacteria get home and food and help animal digest complex carbohydrates and make important vitamins
“Clean-Up Teams”
Bacteria that digest petroleum products
Remove poisonous wastes from water
Manufacturers
Produce foods (cheese, yogurt, butter milk, sour cream, vinegar)
Synthesize drugs through genetic engineering
Insulin, Human Growth Hormone