Bacteria and

Viruses 1

Eubacteria

• ________________________________

• Cell wall contains peptidoglycan (carbohydrate)

• The cell wall protects them from injury and defines their shape

______________________

• Lack the peptidoglycan found in eubacteria

• DNA found in archaebacteria are more like those found in eukaryotes

• ________________________________

Identifying Prokaryotes

• ____________________

• Chemical nature of their cell walls (peptidoglycan)

• ____________________

• The way they obtain nutrients

_____________• Bacilli: Rod shaped bacteria

• Cocci: Round shaped bacteria

• Spirilla: Spiral shaped bacteria

Bacilli

Spirilla 7000X

Cocci

Spirilla 400X

Autotrophs

• ________________: use light energy to convert carbon dioxide and water to carbon compounds and oxygen

• Chemoautotrophs: make organic carbon molecules from carbon dioxide

Metabolic Diversity: ______________________

• Chemoheterotroph: take in organic molecules for both energy and a supply of carbon

• Photoheterotroph: photosynthetic but also must take in organic compounds as a carbon source

Oxygen Supply

• Obligate aerobes: Requires a constant supply of oxygen to live

• Obligate anaerobes: _____________

_______________________________

• Facultative anaerobes: Can survive with or without oxygen

___________________________• Binary fission: This is a type of reproduction in

which the bacterium doubles in size. Once it doubles in size, it replicates its DNA and divides in half.

• Conjugation: Two bacterial cells exchanges DNA through a hollow bridge called pili.

• Endospore: Spore that can remain dormant until favorable conditions for growth arise– Encloses its DNA and cytoplam

– Used to survive

harsh conditions

Conjugation Binary Fission

Importance of Bacteria• Decomposers: _______________________.

• Nitrogen fixers: Nitrogen makes up 80% of the atmosphere. Plants can’t use nitrogen gas directly. Nitrogen is used to make amino acids.

• Human Uses: Used in industry (wine, cheese, make drugs,etc.). – Symbiotic relationship with the intestine.

Disease Bacterium Effect on Body

Strep Throat Streptococcus pyogenes

Fever, sore throat, swollen glands

Tuberculosis Mycobacterium tuberculosis

Fatigue, weight loss, mild fever, night sweats, chronic cough

Tetanus Clostridium tetani Server muscle spasms, paralysis, death

Lyme disease Borrelia burgdorferi “Bulls-eye” rash at site of tick bite, fever, fatigue, headaches, muscle aches, joint aches

Tooth Decay Streptococcus mutans Destruction of tooth enamel

Diseases caused by Bacteria

Virus: What is a virus 1

• ________________

• Particles of nucleic acid (DNA or RNA)

• Protein capsid

• ____________

T4 Bacteriophage

Influenza virus

Tobacco mosaic virus

_______________________

• Host cell DIES in the lytic cycle

1. Virus injects its DNA into the cell2. The cell then makes mRNA from the

genes of the virus3. The viral mRNA is translated into viral

proteins4. The virus uses the materials of the host

cell to make thousands of copies of itself

Lytic (Cont.)5. DNA produces new virus particles

6. Infected cell bursts

7. Releases hundreds of virus particles

8. These particles infect other cells

Lysogenic Cycle

• _________________________________

• Prophage: Viral DNA is embedded in the host’s DNA

• The prophage may remain part of the DNA for years

• Prophage may be activated which removes itself from the host and can produce particles

Lysogenic cycle cont.

Retrovirus

• Retrovirus: Virus that contains RNA instead of DNA

• Genetic material is copied backwards

– RNA to DNA

• _________________

AIDS Virus

Disease Effect on Body Transmission

Influenza body aches, fever, sore throat, fatigue, headache, dry cough

Contact w/ contaminated objects; droplet inhalation

Aids Helper T cells, which are needed for normal immune system, are destroyed

Contact w/ contaminated blood or bodily fluids

Warts Non-cancerous growths on the skin

Contact w/ warts

Polio Fever, headache, muscle weakness, difficulty swallowing

Droplet inhalation

Hepatitis A Jaundice, fatigue, abdominal pain, appetite loss, nausea, diarrhea, joint pain

Human wastes, contaminated water and food

Diseases caused by Viruses