1. Chapter 7
Bacteria

2. Ch 7.1 – What are Bacteria? A. Bacteria – microscopic living cells
1. They live almost everywhere even in extreme environments
2. They are smaller than plant or animal cells

3. 3. They are found in 3 different shapes:
a) Cocci – sphere shaped

4. b) Bacilli – rod shaped
c) Spirilla – spiral shaped

5. 4. Many have whip-like tails called flagella to help them move

6. 5. They reproduce by fission which creates 2 identical cells
6. They can be producers that make their own food or consumers that eat dead organisms

7. a) Consumer bacteria that use oxygen to release energy from their food are called aerobes
b) Bacteria that do not require oxygen are called anaerobes

8. c) Cyanobacteria (blue-green bacteria) – contains chlorophyll and a blue pigment that has the ability to capture light energy and produce food

9. B. Bacteria are classified into 2 kingdoms
1. Eubacteria – the largest and most diverse group of bacteria
2. Archaebacteria – found in very extreme locations (very hot, salty or acidic places)

10. Ch 7.2 – Bacteria in Your Life
A. Most bacteria are helpful rather than harmful
1. Many aid in digestion and produce vitamins
2. Some are grown and used to make medicines (antibiotics)

11. 3. Some bacteria can help clean up the environment in a process called bioremediation
4. Bacterial saprophytes recycle nutrients by using dead organisms as food/energy sources
5. Many types of bacteria can be used in making foods
ex: cheese, yogurt, sauerkraut, pickles

12. B. Bacteria that cause disease are called bacterial pathogens
1. Toxins – poisons produced by some bacterial pathogens
2. Endospores – thick walled structure that surround some pathogens to help them survive in bad conditions

13. a) Food poisoning (botulism & E
a) Food poisoning (botulism & E.coli) and Staphylococcus infections are caused by bacteria that contain endospores

14. C. Treating Harmful Bacteria
1. Sterilization – a process of heating objects to temperatures that kill all bacteria
2. Pasteurization – process used to kill most bacteria in food (sterilization would change taste)

15. 3. Vaccines – can prevent some bacterial infections
a) They are made from damaged or dead bacterial cells