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Chapter 19- BacteriaChapter 19- Bacteria

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I. BacteriaI. Bacteria

A. Classifying ProkaryotesA. Classifying Prokaryotes

  

1. Prokaryotes are organisms 1. Prokaryotes are organisms WITHOUT a nucleus.WITHOUT a nucleus.

  

2. Prokaryotes can be divided into 2. Prokaryotes can be divided into Eubacteria and Archaebacteria.Eubacteria and Archaebacteria.

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B. EubacteriaB. Eubacteria

  

1. The larger of the two kingdoms of 1. The larger of the two kingdoms of prokaryotes is the Eubacteria.prokaryotes is the Eubacteria.

  

2. They live almost everywhere.2. They live almost everywhere.

  

3. Usually surrounded by a cell wall the wall 3. Usually surrounded by a cell wall the wall protects from injury and determines its protects from injury and determines its shape.shape.

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4. The cell wall of Eubacteria 4. The cell wall of Eubacteria contains peptidoglycan a contains peptidoglycan a carbohydrate.carbohydrate.

  

5. Some even have a second 5. Some even have a second membrane outside the cell membrane outside the cell membrane. This makes them VERY membrane. This makes them VERY resistant to damage.resistant to damage.

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C. ArchaebacteriaC. Archaebacteria

  

1. They lack a peptidoglycan and they 1. They lack a peptidoglycan and they have different membrane lipids.have different membrane lipids.

  

2. The DNA sequences of Archae are more 2. The DNA sequences of Archae are more like Eukaryotes then prokaryotes.like Eukaryotes then prokaryotes.

  

3. Most live in extreme environment.3. Most live in extreme environment.

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D. Identifying ProkaryotesD. Identifying Prokaryotes  

1. Prokaryotes are identical by 1. Prokaryotes are identical by characteristics such as shape, the chemical characteristics such as shape, the chemical nature of their cell walls, the way they nature of their cell walls, the way they move and the way they obtain energy. move and the way they obtain energy.

  2. 2. There are three different shapes of There are three different shapes of bacteria.bacteria.

   Rod shaped Bacilli- Rod shaped Bacilli-    CocciCocci   Spirilla Spirilla

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3. Two different types of cell walls are 3. Two different types of cell walls are found in Eubacteria.found in Eubacteria.

  4. Gram staining is used to tell them apart.4. Gram staining is used to tell them apart.

  5. Gram-positive bacteria are purple, they 5. Gram-positive bacteria are purple, they have thicker walls.have thicker walls.

  6. Gram-negative bacteria are red or a 6. Gram-negative bacteria are red or a light pink, they have thinner walls.light pink, they have thinner walls.

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7. Some prokaryotes do not move at 7. Some prokaryotes do not move at all.all.

  

8. Some glide, lash or have slime 8. Some glide, lash or have slime they secrete when they move.they secrete when they move.

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COVER YOUR MOUTH!!!COVER YOUR MOUTH!!!

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COVER YOUR MOUTH!!!COVER YOUR MOUTH!!!

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E. Metabolic DiversityE. Metabolic Diversity

  

1. Heterotrophs- must take in 1. Heterotrophs- must take in food.food.

  

2. Chemoheterotrophs take in 2. Chemoheterotrophs take in organic molecules for energy and a organic molecules for energy and a supply of carbon.supply of carbon.

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3. We are Chemoheterotrophs.3. We are Chemoheterotrophs.

  

4. Photoheterotrophs 4. Photoheterotrophs photosynthesize but also must obtain photosynthesize but also must obtain organic compounds.organic compounds.

  

5. Autotrophs make their own food.5. Autotrophs make their own food.

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6. Photoautotrophs use sunlight to 6. Photoautotrophs use sunlight to make food.make food.

  

7. Chemoautotrophs make food from 7. Chemoautotrophs make food from carbon dioxide but not using the sun carbon dioxide but not using the sun they make it by chemical reactions.they make it by chemical reactions.

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F. Releasing energyF. Releasing energy

1. Bacteria need a constant supply of 1. Bacteria need a constant supply of energy.energy.

  2. Bacteria that need oxygen are called 2. Bacteria that need oxygen are called obligate aerobes.obligate aerobes.

  3. Bacteria that DO NOT NEED oxygen, 3. Bacteria that DO NOT NEED oxygen, actually DIE if there is oxygen present are actually DIE if there is oxygen present are called obligate anaerobes.called obligate anaerobes.

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4. Bacteria that can live with or 4. Bacteria that can live with or without oxygen are called facultative without oxygen are called facultative anaerobes.anaerobes.

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  G. Growth and reproduction- bacteria G. Growth and reproduction- bacteria reproduce three different ways.reproduce three different ways.

  

1. Binary fission- Bacteria grows and 1. Binary fission- Bacteria grows and grows and splits in half. Exact copes.grows and splits in half. Exact copes.

  

2. Conjugation- bacteria exchange 2. Conjugation- bacteria exchange genetic information.genetic information.

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3. Spore formation- when growth conditions 3. Spore formation- when growth conditions become unfavorable many bacteria produce become unfavorable many bacteria produce spores. spores.

  a. One type of a spore is called an endospore.a. One type of a spore is called an endospore.

  b. Spores can remain dormant for months. b. Spores can remain dormant for months.

  c. When conditions improve, the endospore c. When conditions improve, the endospore will germinate and the bacterium will grow will germinate and the bacterium will grow again. again.

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H. Importance of bacteriaH. Importance of bacteria

1. Bacteria are vital to maintaining the 1. Bacteria are vital to maintaining the living world. living world.

2. Some are producers that capture 2. Some are producers that capture energy by photosynthesis.energy by photosynthesis.

  3. Others are decomposers breaking 3. Others are decomposers breaking down nutrients in dead matter.down nutrients in dead matter.

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4. 4. Bacteria breakdown dead and Bacteria breakdown dead and decaying organisms.decaying organisms.

  5. Help to recycle nutrients – which 5. Help to recycle nutrients – which helps to maintain equilibrium in the helps to maintain equilibrium in the environment.environment.

  6. Bacteria also help perform critical 6. Bacteria also help perform critical steps in sewage treatment.steps in sewage treatment.

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Flesh eating bacteriaFlesh eating bacteria

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7. 7. Others have human uses.Others have human uses.  

8. Bacteria convert nitrogen gas into a 8. Bacteria convert nitrogen gas into a form plants can use, this is called nitrogen form plants can use, this is called nitrogen fixation. fixation.

  9. Nitrogen fixation allows nitrogen atoms 9. Nitrogen fixation allows nitrogen atoms to continually cycle through the biosphere.to continually cycle through the biosphere.

  10. Bacteria are also used to make some 10. Bacteria are also used to make some foods such as: pickles, ice cream, yogurt, foods such as: pickles, ice cream, yogurt, and other things.and other things.

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II. VirusesII. Viruses

A. What is a virus?A. What is a virus?  

1. A typical virus is composed of a 1. A typical virus is composed of a core DNA or RNA surrounded by a core DNA or RNA surrounded by a protein coat.protein coat.

  2. A virus’s protein coat is called its 2. A virus’s protein coat is called its capsid.capsid.

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3. The capsid includes proteins that 3. The capsid includes proteins that enable a virus to enter a host cell. enable a virus to enter a host cell.

  

4. Viruses that infect bacteria are 4. Viruses that infect bacteria are called bacteriophages.called bacteriophages.

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B. Viral infectionsB. Viral infections  

1. 1. Once a virus is inside the host cell, Once a virus is inside the host cell, two different processes may occur.two different processes may occur.

  2. Lytic cycle- virus enters a cell, 2. Lytic cycle- virus enters a cell, makes copies of it and causes the makes copies of it and causes the cell to burst.cell to burst.

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3. Lysogenic infection- a virus 3. Lysogenic infection- a virus integrates its DNA into the DNA of integrates its DNA into the DNA of the host cell, and the viral genetic the host cell, and the viral genetic information replicates along with the information replicates along with the hosts cell’s DNA.hosts cell’s DNA.

  4. The viral DNA that is embedded in 4. The viral DNA that is embedded in the host’s DNA is called a prophage.the host’s DNA is called a prophage.

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C. C. RetrovirusesRetroviruses

  

1. Some viruses contain RNA as their 1. Some viruses contain RNA as their genetic information and are called genetic information and are called retroviruses. retroviruses.

  

2. When retroviruses infect a cell, they 2. When retroviruses infect a cell, they produce a DNA copy of their RNA.produce a DNA copy of their RNA.

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3. The DNA is inserted into the host 3. The DNA is inserted into the host cell they will infect.cell they will infect.

4. Retroviruses get their name 4. Retroviruses get their name because their genetic information is because their genetic information is copied backwards.copied backwards.

  5. Usually DNA-RNA, but retrovirus 5. Usually DNA-RNA, but retrovirus goes RNA-DNAgoes RNA-DNA

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D. Viruses and living cellsD. Viruses and living cells

  

1. Viruses must infect a living cell in 1. Viruses must infect a living cell in order to grow and reproduce.order to grow and reproduce.

  

2. Are viruses alive?2. Are viruses alive?

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III. Diseases III. Diseases

A. Bacterial Disease in HumansA. Bacterial Disease in Humans

  

1. Disease causing agents are called 1. Disease causing agents are called pathogens.pathogens.

  

2. Bacteria produce disease in one 2. Bacteria produce disease in one of two ways.of two ways.

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3. Some bacteria damage the cells and 3. Some bacteria damage the cells and tissues of the infected organisms directly tissues of the infected organisms directly by breaking down the cells for food.by breaking down the cells for food.

  4. Other bacteria release toxins that 4. Other bacteria release toxins that travel throughout the body interfering with travel throughout the body interfering with the normal activity of the host.the normal activity of the host.

  5. Tuberculosis- TB is inhaled into the 5. Tuberculosis- TB is inhaled into the lungs and destroys lung tissue.lungs and destroys lung tissue.

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6. Bacteria also release toxins in the 6. Bacteria also release toxins in the body, like strep throat. body, like strep throat.

  7. These toxins if go untreated could 7. These toxins if go untreated could cause scarlet fever.cause scarlet fever.

  8. Diphtheria also infects the throat. It 8. Diphtheria also infects the throat. It releases toxins and if it goes untreated releases toxins and if it goes untreated could cause breathing problems, heart could cause breathing problems, heart failure, paralysis and death.failure, paralysis and death.

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9. A vaccine is a preparation of 9. A vaccine is a preparation of weakened or killed pathogens.weakened or killed pathogens.

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body will produce immunity to the body will produce immunity to the disease.disease.

  11. Immunity is the body’s ability to 11. Immunity is the body’s ability to destroy new pathogens.destroy new pathogens.

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12. Antibiotics are drugs that can attack 12. Antibiotics are drugs that can attack and destroy the invading bacteria.and destroy the invading bacteria.

  

13. Bacterial diseases also affect animals.13. Bacterial diseases also affect animals.

  

14. There are various methods used to 14. There are various methods used to control bacteria growth- sterilization control bacteria growth- sterilization disinfectants and food processing.disinfectants and food processing.

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15. Viruses produce disease by disrupting 15. Viruses produce disease by disrupting the body’s normal equilibrium. the body’s normal equilibrium.

  

16. Viruses attack and destroy certain 16. Viruses attack and destroy certain cells in the body, causing the symptoms of cells in the body, causing the symptoms of the disease. the disease.

  

17. Many viruses infect plants also.17. Many viruses infect plants also.

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18. Many plants, like potatoes, 18. Many plants, like potatoes, tomatoes, apples and citrus fruits tomatoes, apples and citrus fruits can be infected by viroids.can be infected by viroids.

  

19. Viroids are single stranded RNA 19. Viroids are single stranded RNA molecules that have no surrounding molecules that have no surrounding capsid. capsid.

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20. Prions are short for protein 20. Prions are short for protein infectious particles. infectious particles.

  

21. Mad cow disease is thought to 21. Mad cow disease is thought to be caused by Prions.be caused by Prions.

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22. Bird flu is a virus.22. Bird flu is a virus.

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The EndThe End