1. Chapter 13: Bacteria and Viruses
Essential question: How do bacteria and viruses affect our lives?

2. I. Prokaryotes: single celled organisms that do not have nucleus
A. Domains: Archaea and Bacteria
1. Bacterial fossils found are about 3.5 billion years old
2. Evolved into many different forms and live in almost every environment

3. Concept Map Section 19-1 Bacteria Go to Section:
are classified into the kingdoms of
Eubacteria
Archaebacteria
include a variety of lifestyles such as
live in harsh environments such as
Infecting large organisms
Thick mud
Living in soil
Animal digestive tracts
Salty lakes
Hot springs
Go to Section:

4. B. Classification
1. Domain Bacteria: Kingdom Eubacteria: often called bacteria
a) many different shapes and sizes
b) shapes: bacilli – rod shaped, cocci-spherical, and spirilla- spiral

5. c) Gram-negative bacteria: complex cell wall and small amounts of peptidoglycan (protein-carbohydrate compound)
d) Gram-positive bacteria: simpler and have more peptidoglycan
Gram stain

7. 2. Domain Archaea: Kingdom Archaebacteria: more ancient
a) unusual lipids in cell membrane and no peptidoglycan in their cell walls
b) live in extreme environments
c) methanogens: get energy by changing H2 and CO2 into methane gas
d) extreme halophiles: live in high salt concentrations
e) thermoacidophiles: acidic and high temperature environments

8. Archaebacteria at Yellowstone National Park
Morning Glory Hot Spring

9. Grand Prismatic Spring
Fumarole with sulfur

10. Mammoth Hot Springs

11. Mud Pots

12. Imperial Geyser

13. II. Biology of Bacteria
A. Structure
1. Cell wall: most bacteria have a cell wall
2. Cell membrane and cytoplasm: lipid bilayer
a) carries out cellular respiration
b) photosynthesis if it is a photosynthetic bacteria
c) cytoplasm: contains ribosomes and DNA

14. 3. Capsules: outer covering that helps to protect bacteria from drying out or harsh chemicals
4. Pili: short, hairlike protein structures helps bacteria cling to host cells Pili
5. Endospores: dormant structure that is produced during harsh environmental conditions
6. Movement structures
a) flagella
b) glide through slime layer

15. 7. DNA: single closed loop of double-stranded DNA attached to the cell membrane
a) plasmid: small circular loops of DNA that carry genes that enable the bacteria to cause disease or resist antibiotics
bacteria

16. The Structure of a Eubacterium
Section 19-1
Peptidoglycan
Cell wall
Cell membrane
Ribosome
Flagellum
DNA
Pili
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17. Extra Credit Option : Due Fri. Feb. 12
Watch the movie Contagion
Write a summary (paragraph) about the movie by answering the following questions
Where did the virus come from (country, animal species, original two people)
How was the virus spread?
Why did it spread so quickly?
Why did it take so long to make a vaccine?

18. Nutrition and growth
1. Heterotrophs and autotrophs
2. Phototrophs: get energy from light
3. Chemotrophs: get energy from chemicals taken from the environment

19. 4. Four ways
a) photoheterotroph: uses light but gets its carbon from organisms
b) chemoheterotroph: obtains energy and carbon from other organisms
c) photoautotroph: uses light energy and gets carbon from CO2
d) chemoautotroph: energy from compounds and gets carbon from CO2

20. C. Prokaryotic habitats
1. Obligate anaerobes: cannot survive in oxygen
2. Facultative anaerobes: can live with or without oxygen
3. Obligate aerobes: require oxygen

21. D. Genetic recombination: three nonreproductive ways that bacteria get new genetic material
1. Transformation: takes in DNA from its environment Transformation
2. Conjugation: two living bacteria bind together and one transfers genetic information to the other
Conjugation
3. Transduction: virus obtains DNA from a host and as the viruses replicates inside the bacteria the new DNA is added Transduction

22. III. Bacteria and Humans
A. Bacteria and Disease
1. Pathology: study of diseases
2. Pathogen: bacteria that cause disease
3. Toxins: poisons produced by bacteria that cause disease
4. Bacteria can cause disease by destroying body tissue

23. Common Diseases Caused by Bacteria
Section 19-2
Common Diseases Caused by Bacteria
Disease
Pathogen
Prevention
Tooth decay
Lyme disease
Tetanus
Tuberculosis
Salmonella food poisoning
Pneumonia
Cholera
Streptococcus mutans
Borrelia burgdorferi
Clostridium tetani
Mycobacterium tuberculosis
Salmonella enteritidis
Streptococcus pneumoniae
Vibrio cholerae
Regular dental hygiene
Protection from tick bites
Current tetanus vaccination
Vaccination
Proper food-handling practices
Maintaining good health
Clean water supplies
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24. 5. Antibiotics: drugs that combat bacteria by interfering with various cellular functions
6. Antibiotic resistance: bacteria most susceptible to the antibiotic die first, but some are resistant and grow
Resistance

25. B. Useful bacteria
1. Decomposers: break down remains of organic matter in dead plant and animal waste allowing organic compounds to become available to other organisms
2. Used in sewage treatment plants
3. Producing and processing food like sour cream, yogurt, cheese, pickles, and sauerkraut Foods

26. 4. Industrial chemical production: mining for minerals and petroleum, insecticides, cleaning up oil spills

27. Bacteria Health Pamphlet
1. Title and pictures
2. List several ways to prevent disease
3. Antibiotics used to treat bacterial disease
List several ways that bacteria are helpful to humans
5. List several examples of bacterial diseases (p. 472)

28. IV. Virus Structure
A. Virus: nonliving particle composed of DNA or RNA and a protein coat
1. Virology: study of viruses
B. Characteristics of viruses
1. One of the smallest biological particles capable of causing diseases

29. 2. Viruses can only replicate by infecting cells and using the cell’s organelles to make new virus particles
3. Made up of nucleic acid (DNA or RNA) and protein coat called capsid
4. Shapes: helical and icosahedral (20 triangular faces)
5. Classified by whether they have RNA or DNA and whether it is singled and double stranded
Virus

30. Virus Structures Section 19-3 Tobacco Mosaic T4 Bacteriophage Virus
Influenza Virus
RNA
Capsid
proteins
Head
Tail sheath
DNA
Tail fiber
RNA
Capsid
Surface
proteins
Membrane
envelope
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33. V. Viral Replication
A. Bacteriophage: viruses that infect bacteria
1. Structure: icosahedral head with tail and tail fibers Bacteriophage
B. Lytic cycle lytic
1. Virus invades a host by injecting its DNA
2. Produces new viruses
3. Cell breaks open and releases the new viruses

34. Figure 19-14 The Lytic Cycle
Section 19-3
Bacteriophage protein coat
Bacteriophage DNA
Bacterial
chromosome
Bacteriophage attaches to bacterium’s cell wall
Bacteriophage enzyme lyses the
bacterium’s cell wall, releasing
new bacteriophage particles that
can attack other cells.
Lytic Cycle
Bacteriophage injects DNA into bacterium
Bacteriophage proteins and nucleic acids assemble into complete bacteriophage particles
Bacteriophage
Bacteriophage DNA
Bacteriophage protein
Bacteriophage takes over bacterium’s metabolism, causing synthesis of new bacteriophage proteins and nucleic acids
Go to Section:

35. C. Lysogenic cycle
1. Virus injects DNA into cell
2. DNA integrates into the host cell’s DNA
3. DNA of host cell replicates and so does the virus’s DNA
4. Each bacterial offspring will be carrying the DNA of the virus
5. At some point the cell will go into the lytic phase and destroy the cell Lysogenic

36. A Lysogenic Infection Section 19-3 Go to Section: Lytic Cycle
Bacterial
chromosome
Bacteriophage DNA
Bacteriophage injects DNA into bacterium
Bacteriophage DNA (prophage) can exit the bacterial chromosome
Lytic Cycle
Lysogenic Cycle
Bacteriophage DNA (prophage) may replicate with bacterium for many generations
Bacteriophage enzyme lyses the bacterium’s cell wall, releasing new bacteriophage particles that can attack other cells
Bacteriophage DNA forms a circle
Prophage
Bacteriophage proteins and nucleic acids assemble into complete bacteriophage particles
Bacteriophage DNA inserts itself into bacterial chromosome
Go to Section:

37. VI. Viruses and Human Disease
A. Infectious diseases: can affect various organs in the human body including brain, liver, heart, lungs, and skin
1. Common cold, chickenpox, measles
2. Mumps, polio, rabies, AIDS, and hepatitis

38. 3. Some viruses can cause cancer by blocking the normal controls on cell reproduction
a) HPV: human papillomarvirus can cause cervical cancer (there is a vaccine for this virus)
b) hepatitis B can cause liver cancer

39. Common Diseases Caused by Viruses
Section 19-3
Common Diseases Caused by Viruses
Type of Virus
Nucleic Acid
Disease
Oncogenic viruses
Retroviruses
Adenoviruses
Herpesviruses
Poxviruses
DNA
RNA
cancer
cancer, AIDS
respiratory infections
chickenpox
smallpox
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40. 4. Emerging disease: illnesses caused by new or reappearing infectious agents that typically exist in animal populations
a) wild and domestic animals can have viruses that can be transmitted to people
b) Avian or bird flu is due to close interaction of people and poultry on farms and in markets around the world

41. B. Prevention and treatment
1. Vaccines: prevent the disease by giving inactive virus to stimulate the body’s immune system to provide protection against the pathogen
2. Antiviral drugs: given to infected patients and it interferes with viral nucleic acid synthesis (very few types of drugs)
3. Antibiotics can not destroy viruses, only bacteria
Vaccine

42. 4. 4. Vector control: control of animal vectors that carry the virus
a) Mosquito control to stop yellow fever
b) Rabies vaccinations to keep pets from of rabies and prevent spread to humans

43. Virus Research
Answer the following questions using the reference books on the lab tables. Research 1 viral diseases.
Name of the viral disease
Where is it found in the world?
Is there a vaccine or way to prevent?
What are 2 symptoms of the disease?