Prokaryotes and Viruses

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Chapter 11

• Prokaryotes and Viruses

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Ch 11 Major Concepts

• Prokaryotes lack nuclei and membrane enclosed
  organelles
• Bacteria occupy every niche
• Archebacteria may be the most ancient of all
  organisms
• Bacteria cause some disease
• Most bacteria are beneficial and essential to
  ecosystem

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MC cont.

• Viruses are transmitted by sexual contact
• Viruses have profound effects on organisms
• AIDS, caused by the HIV virus, is a world wide
  health problem

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Prokaryotes and Viruses

• Microscopic organisms found everywhere
• Producers, consumers, or decomposers
• Humans diseases

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11.1 Prokaryotes

• Very small- spoon full of soil has 10 billion
• Great in mouth, gt humans ever lived on earth
• Single celled
• Shapes rod, sphere, or spiral
• Flagella
• Examples Rickets, rocky mtn fever from ticks

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• Reproduce
• Asexually (copy DNA, divide) like mitosis
• Sexually Conjugation (transfer of DNA)
• Two major Kingdoms
• Archaebacteria ancient
• Eubacteria true bacteria

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Prokaryote Structure

• You have this from MONDAY. Attach to this packet.

Simple structure, complex function
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• 1 chromosome attached to membrane
• 1 or more circular DNA (plasmids)
• Plasmid- few genes, used by scientists in labs to
  engineer cells
• Group digest anything
• Decomposers essential to food web
• Fossils 3.5 bill. years ago
• Live everywhere (cold? hot), acid, salt

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11.2 Archaebacteria

• Unique ribosomes
• 1st organisms on earth
• Harmless to humans (NOT pathogens)

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11.3 3 Types of Archaebacteria

• Thermoacidophiles- live in hot, acidic
  environment
• Halophiles- require high Na sodium ion
• Grow in salt brine, Great Salt Lake
• Spoils fish, some photosynthetic
• Methanogens- anaerobic (oxygen will kill them)
• Produce CH4 gas from H2 and CO2
• Found in stagnant H2O, ocean bottom, hot springs,
  sewage treatment
• Part of carbon cycle
• Found in human and cattle digestive system
• Energy source CH4 from organic waste

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11.4 Eubacteria Diverse Group

• Aerobic or Anaerobic
• Photsynthetic or Chemosynthetic, thermophilic
  (many cultured at 37C, body temp)
• 3 types
• Gram ? thick cell wall (peptidoglycan)
• Gram - ? thin cell wall
• Mycoplasms ? NO Cell Wall
• Green, purple or cyanobacteria

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Gram (stain)
Gram - ( NO stain)
mycoplasma
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11.5 Eubacteria Nitrogen Cycle

• Some make own food from inorganic material
• Chemosynthetic
• N2 cycle
• Nitrifying bacteria live in root nodules, turn N2
  into NO3

N2 inorganic
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Symbiosis bacteria w/ plant root (legumes have
many)
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11.6 Disease

• disease condition that interferes w/ organisms
  ability to perform vital function
• Pathogen
• Host
• Resistance
• Virulence
• Immunity
• Antibodies
• Vaccines

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11.7 Some Eubacteria are pathogens

• Most are beneficial or harmless
• Some pathogenic spread through food, water or
  air
• No Archae are known to cause disease
• Plant example fireblight
• Human Cholera, TSS, dental carries (cavities)
• Sneezes 200mph, 10-100K eubacteria!