1. Daily Questions 1. What is the difference between binary fission and conjugation? 2. What are obligate anaerobes? 3. Archaebacteria belong to the domain _________________.

2. Daily Questions 1. What is a virus? 2. Name the three ways bacteria can reproduce. 3. Most bacteria are (heterotrophs/autotrophs).

3. Daily Questions 1.What is a phylum? 2.List Linnaeus’ 7 taxons in order from largest to smallest. 3. Name the three domains.

4. Daily Questions 1. What are the 4 ways bacteria can move? 2. What are chemoautotrophs? 3. What are photoheterotrophs?

5. Daily Questions 1. What is the difference between Archaebacteria and Eubacteria? 2. Your doctor says you have pneumonococcus. What shape of bacteria is this? 3. Your doctor says you have a “staph” infection. What do you know about this bacteria?

6. Chapter 19 Bacteria and Viruses

7. I. Prokaryotes A.Prokaryotes: single-celled organisms that lack a nucleus 1. Eubacteria – walls contain peptidoglycan (a carbohydrate) 2. Archaebacteria – lack peptidoglycan, DNA similar to eukaryotes, have different cell membrane lipids

8. Prokaryotic Body Plan bacterial flagellum pilus capsule cell wall plasma membrane ribosomes in cytoplasm

9. B.Identifying Prokaryotes 1. Shapes a. Bacilli (rod shaped) a. Bacilli (rod shaped) b. Cocci (spherical) b. Cocci (spherical) c. Spirilla (spiral) c. Spirilla (spiral)

10. 2. Cell Walls a. Gram-positive (w/peptidoglycan) – purple b. Gram-negative (w/o peptidoglycan – red

11. 3. Arrangement a.Staphyl: Clumps or clusters b. Strepto: long chains

12. 4. Movement a.Propelled by tail-like structure called flagella b. Glide along a slime secretion c. Move along like snakes d. Some don’t move

13. C.Obtaining Energy 1. Autotrophs a. Photoautotrophs: obtain energy from photosynthesis a. Photoautotrophs: obtain energy from photosynthesis b. Chemoautotrophs: obtain energy from inorganic molecules b. Chemoautotrophs: obtain energy from inorganic molecules

14. 2. Heterotrophs a. Can cause food poisoning b. Photoheterotrophs: photosynthetic, but also need organic compounds for nutrition

15. D.Releasing Energy 1. Obligate aerobes: require oxygen 2. Obligate anaerobes: cannot live in presence of oxygen 3. Facultative anaerobes: do not need oxygen, but can live in the presence of it

16. E.Growth and Reproduction 1. Binary fission: cell divides, asexual 2. Conjugation: transfer of genetic information from one cell to another, sexual 3. In unfavorable conditions, many bacteria can form endospores – can remain dormant for months or years (such as anthrax)

17. Prokaryotic Fission The bacterial chromosome is attached to the plasma membrane before DNA replication Replication starts and proceeds in two direction from some point in the bacterial chromosome The DNA copy is attached at a membrane site near the attachment site of the parent DNA molecule The two DNA molecules are moved apart by membrane growth between the two attachment sites New membrane and new wall material are added transversely, through the cell’s midsection The ongoing, orderly deposition of membrane and wall material at the midsection cuts the cell in two

18. Conjugation nicked plasmid in donor cell conjugation tube to recipient cell Conjugation tube forms between a donor and recipient. An enzyme nicks the plasmid Plasmid DNA replication starts. The free DNA strand starts moving through tube In the recipient cell, replication starts on the transferred DNA The cells move apart and the plasmid in each forms a circle

19. II. Bacteria in Nature A.Decomposers 1. Help recycle nutrients – break down dead organisms 2. Used in sewage treatment

20. B.Nitrogen Fixers 1. Nitrogen fixation: converting nitrogen into a form plants can use 2. Rhizobium grow on roots of soybeans and other legumes – converts nitrogen to ammonia for the plant

21. C.Bacteria and Disease 1. Pathogen: disease-causing agents 2. 2 ways bacteria cause disease a. Break down tissues for food b. Release toxins 3. Many can be prevented with vaccines, can be treated with antibiotics

22. D.Human Uses of Bacteria 1. Food – cheese, yogurt, buttermilk, sour cream, pickles, sauerkraut 2. Industry – cleaning up oil spills, mining minerals, synthesizing drugs

23. 3. Bacteria live in our digestive tract to help in digestion (called normal flora)

24. E.Controlling Bacteria 1. Sterilization: destroy bacteria by subjecting them to great heat or chemicals a. Boiling, frying, steaming can all kill bacteria b. Disinfectant chemical solutions can be used in homes and hospitals 2. Refrigeration – bacteria grow slowly at low temperatures

25. III. Viruses A.Viruses: particles of nucleic acid and protein 1. Nucleic acid = DNA or RNA that contains instructions for making new copies of the virus 2. Capsid: outer protein coat

26. DNA and RNA DNA – deoxyribonucleic acid chemical compound (a nucleic acid, which contains hydrogen, oxygen, nitrogen, carbon, and phosphorus) with instructions for coding proteins that determines your genetic makeup RNA – ribonucleic acid nucleic acid that contains the sugar ribose

27. B.Viral Infection 1. Infect cells and replicate inside host cell 2. Bacteriophage: viruses that infect bacteria

28. 3. 2 types of viral infections a. Lytic infection: virus enters cell, make copies of itself and causes the cell to burst b. Lysogenic infection: virus embeds its DNA into DNA of host and is replicated with host cell’s DNA

29. C.Viruses and Disease 1. Many viruses can be prevented through the use of vaccines (polio, measles, influenza) measles, influenza) 2. Oncogenic viruses cause cancer 3. Retroviruses contain RNA 4. Prions contain no DNA or RNA, only protein

30. The Prophage Prophage = viral DNA that is inserted into a cell The prophage can have the cell make copies of the virus right away or may wait several generations (a latent infection) and then begins making copies at a later time