Prokaryotes

1. Prokaryotes

2. What We Need to Learn! • Key characteristicsof members of the kingdom archaebacteria and kingdom eubacteria • Structure (how they are built) • Type of nutrition and growth • Bacteria and disease • Useful bacteria

3. Kingdoms of Bacteria • Two main groups the Archaebacteria and the Eubacteria • What do we already know about these?

4. Archaebacteria Extreme Bacteria

5. Archaebacteria Characteristics • 3.5 billion years old • Live in extreme conditions • Nonpathogenic • Differ from eubacteria • Cell membranes are built from different types of fats • Cell walls are built from different carbohydrates than the eubacteria. • There are three main groups • Methanogens • Extreme halophiles • Extreme thermoacidophiles/thermophile

6. Eubacteria True Bacteria

7. Eubacteria Characteristics - Energy Eubacteria get their energy and nutrition in many different ways • Aerobic and anaerobic • Anaerobes is any organism that does not require oxygen for growth ex. Clostridium butyricum • Aerobes require oxygen • Producers • Photosynthetic • Chemosynthetic • Consumers • Symbiotic • Parasitic • Saprophytic

8. General Characteristics of Bacteria • Bacterial shapes • Bacillus – rod shaped • Coccus- spherical • Spirilla – corkscrew • Staphylococci – clusters of cocci bacteria • Streptococci- chains of cocci bacteria • Reproduction • asexually by binary fission

9. Binary Fission • http://www.youtube.com/watch?v=DY9DNWcqxI4

10. Structure of Bacterial Cells • Smaller than plant and animal cells • Have cell membranes that surround their cytoplasm • Inside the bacterial cells there is a chromosome, ribosomes and sometimes an extra circular piece of DNA called a plasmid • No cell membrane-bound organelles (prokaryotic)

11. Other Features of Bacteria • Endospores- some bacteria are able to produce spores that are capable of withstanding harsh conditions. • Motility- some bacteria move by use of a flagella. Some spiral shaped bacteria move by a corkscrew motion, others can contract and slide along ex. Myxobacteria • Some eubacteria are pathogenic

12. E. Coli Moving • http://www.youtube.com/watch?v=2P9hvlsF9_c

13. Types of Eubacteria • Eubacteria can be divided into at least 12 phyla’s, we will look at 4 • First 3 major divisions based upon cell wall 1. Mycoplasma • No cell wall • Smallest microorganisms capable of independent growth. • Some are pathogenic causing pneumonia in humans and cattle

14. 2. Gram positive bacteria • Thick cell walls • Widespread in soil and air • Used in the preparation of food products such as sauerkraut, buttermilk, and yogurt • Some are a source of antibiotics • Responsible for tooth decay 3. Gram Negative bacteria • Thin Cell wall -Tend to be antibiotic resistant • Responsible for strep throat • Many are photosynthetic and anaerobic

15. 4. Cyanobacteria • Blue/green bacteria – photosynthetic-contain chlorophyll but it is not in a chloroplasts • Aerobes • Can cause green color in polluted lakes-bloom • Helped put oxygen in primitive atmosphere

16. Pathogenic Bacteria • Some eubacteria cause disease • Enter the body in a number of ways • Some produce toxins • Bacterial infections can be treated with antibiotics(cure) and vaccines(preventative) • Safety of the foods we eat have improved due to pasteurization, radiation, canning, refrigeration, FDA, etc

17. Beneficial Bacteria • Some bacteria produce antibiotics. Why? • Answer: Antibiotics inhibit the growth of other rival bacteria • Bacteria are decomposers – saprophytes. • They recycle nutrients and rid our world of dead material. ex. nitrogen and carbon • Some bacteria can be used to clean up environmental pollutants and waste- bioremediation – ex. Oil spills

18. Beneficial Bacteria (con’t) • Help produce some of the foods we eat such as yogurt, sour cream, cheese, sauerkraut, sugar syrups….. • Used in the production of medicines, enzymes, cleansers and adhesives. • Methane produced by bacteria is used as fuel.