1. The effects of Antibiotics on the growth of bacteria intro http://outreach.mcb.harvard.edu/animations/resistance7.swf

2. How do bacteria reproduce? Binary fission: to divide in half http://www.ryancshaw.com/Files/micro/Animations/BacterialGrowth/PLAY _bacterial_growth.html

3. How do bacteria reproduce?

4. Parent cell produces genetically identical daughter cells –unless mutation changes DNA (rare but happens)

5. How do bacteria reproduce? Exponential growth –bacteria at appropriate temperature w/ nutrients can reproduce every 20 minutes

6. How do bacteria reproduce? Exponential growth –In 24 hours 1 cell --> 4,722,400,000,000,000,000,000

7. How do scientists grow bacteria? Petri Dish with solid agar nutrition

8. How do scientists grow bacteria? Flask or test tube with liquid nutrients

9. Antibiotics Drugs produced by bacteria or fungi to treat people with bacterial infections (does not treat viral infections)

10. Antibiotics Most antibiotics come from microorganisms –chemical warfare to keep foreign microbes out of territory and away from food

11. Antibiotics Example: different Streptomyces strains which naturally grow in soil produce: streptomycin, erythromycin and tetracyline

12. Antibiotic resistant bacteria Bacteria that have a gene or genes that allow them to survive the antibiotic

13. Antibiotic resistant bacteria How do individual bacteria develop resistance? –Random mutation hidden in genes

14. Antibiotic resistant bacteria And “bacteria sex”– conjugation: bacteria of different or same species can exchange pieces of DNA sometimes including mutation

15. If mobile plasmid Includes an antibiotic resistance Gene, then the recipient bacterium Will transform into An antibiotic resistant strain http://highered.mcgraw- hill.com/sites/9834092339/student_view0/chapte r28/bacterial_conjugation.html

16. Antibiotic resistant bacteria Resistance not always 100%

17. Antibiotic resistant bacteria 2 types of bacteria –gram (+): stain violet because of cell wall components –http://www.microbelibrary.org/microbelibrary/files/ccIm ages/Articleimages/keen/Gramstainkeen.htmhttp://www.microbelibrary.org/microbelibrary/files/ccIm ages/Articleimages/keen/Gramstainkeen.htm

18. Antibiotic resistant bacteria 2 types of bacteria –gram (-): stain red because of cell wall components. This cell wall can be toxic and more resistant to antibiotics

19. Antibiotic resistant bacteria

20. Lab Purpose: to determine which antibiotic is the most effective in limiting the growth of the bacterial species Bacillus subtilis (that was grown from a peppercorn source) BioRad Modified Kirby-Bauer Test http://www.cleanvideosearch.com/media/action/yt/watch?videoId=CaeQaAuG9pU