1. Bacteria
BACTERIA

3. Bacteria (Monerans)– Kingdoms Archaebacteria and Eubacteria
There are more bacteria on Earth than stars in the sky!
The closest estimate is that there are 5 million trillion trillion bacteria on Earth – that’s a 5 with 30 zeroes after it.
Bacteria produce the air we breathe, clean the water we drink, and create fertile soil.
Less than one percent of bacteria cause diseases.

4. Bacteria structure – prokaryotic cell
plasmid

5. Bacteria Growth Curve

6. Most bacteria die when conditions get bad:
These conditions could be a change in temperature, loss of food, change in pH, etc.
Some bacteria can preserve themselves during bad times, then they can regrow and resume their lives. They do this by producing an endospore.
Endospores can preserve the cell’s DNA until conditions get better again. They are resistant to all the bad conditions.

7. Steps in formation of an endospore
Endospore production – preserves the cell during hard times– not a form of reproduction
Steps in formation of an endospore

8. Endospore
Bacteria that are harmful to humans and that form endospores:
Clostridium tetani – causes tetanus
Clostridium botulinum – causes food deadly poisoning

9. Binary Fission – bacteria can divide as often as every 20 minutes!

10. Origin of Monerans Archaebacteria
usually found in harsh environments – hot, salty, smelly!
Ancient – probably resemble the first bacteria

11. Methanogens
produce methane – live in digestive tract of mammals, in swamps and sewage.

12. thermophiles
can live in extremely hot water – found in hot springs

13. halophiles
Live in very salty water, such as the Great Salt Lake in Utah and the Dead Sea

14. Eubacteria – true bacteria
Many types – modern bacteria
Classification is by:
Cell shape
Cell wall composition
Nutrition
Respiration

15. Cell Shape
Coccus - round
Bacillus - rod
spirillum

16. Names can tell a lot about the bacterial growth
Some bacteria grow alone
Diplo…means two
Diplococcus
Diplobacillus or
Strepto… means chain
- as in streptococcus
- and streptobacillus
Staphylo… means cluster
As in staphlyococcus

17. Cell Wall Composition – gram positive or gram negative
Gram Positive Gram negative
Stains blue stains pink

18. Nutrition – Autotrophic or Heterotrophic
Autotrophs –
make their own food
Use sun’s energy or chemical energy

19. Most Monerans are Heterotrophs
Escherichia coli
spirillum
anthrax

20. Respiration – process of getting energy from food
Aerobic
Need oxygen
Can’t live without oxygen = obligate aerobes
EX – TUBERCULOSIS BACTERIUM
Prefers to live with oxygen = facultative aerobes
Tb lung

21. Anaerobic – don’t need oxYgen SOME CAN’T SURVIVE WITH OXYGEN –
THESE ARE OBLIGATE ANAEROBES
EX – TETANUS
This baby probably got tetanus from honey – don’t give honey to a baby!

22. SOME CAN LIVE WITH OXYGEN BUT PREFER TO LIVE WITHOUT IT – fACULTATIVE ANAEROBES
E. coli

23. How Important are bacteria to the world?
Decomposition – most important function for living things. What happens to all the dead bodies?
Here is a bacterium
of decay

24. Food web

25. Nitrogen cycle

26. Cow Digestion
Bacteria in the stomach

27. Tooth Decay
Don’t forget to brush and floss your teeth!

28. Foods from bacteria
cheese
yogurt
sauerkraut

30. What conditions do bacteria need for the best growth?
Food source (your soup is good)
Proper temperature - human pathogens (disease causers) live best at 98.6 F.
Moisture
Oxygen (aerobes) or not (anaerobes)
Change any of these and the growth of bacteria can be slowed down or stopped.

31. We compete with bacteria for our food – they eat the same stuff we do…
We compete with bacteria for our food – they eat the same stuff we do…. How do we preserve our food?
Drying (prunes)
salting
refrigeration
pickling
freezing

33. Diseases caused by bacteria
Anthrax – a natural pathogen that can be used for bioterrorism

34. Lyme disease – causes illness and can lead to arthritis

35. plague
gonorrhea
Strep throat

36. Food poisoning
Salmonella food poisoning – from eggs, chicken, mayonnaise
Botulism – from improperly canned foods

38. Antibiotics, if used cautiously, can cure bacterial infections

39. Antibiotics are tested using Petri dishes and paper soaked in the antibiotic – anywhere the antibiotic inhibits growth, a zone of inhibition will be seen
Most effective
Not effective

40. Here is a white blood cell attacking a bacillus

42. Uses of bacteria other than food production
Bioremediation – using microorganisms to rid environment of harmful substances
Ex – oil spill site
Hazardous waste site
Sewage treatment

43. Medical uses of bacteria
Genetic engineering to produce medical products –
Insulin
Human growth hormone
Gene for human insulin or hgh
Now all cells will have the gene and will make the product

44. That’s all folks!