Biology: Archaea

  1. Archaea used to be considered a bacteria until what difference was discovered by Carl Woese?
    Discovered that the rRNA sequences were difference between Archaea and Bacteria.

    *Chose to compare rRNA because ANY changes in rRNA probably occur at a slow, steady pace as evolution occurs.
  2. Which are believed to be more closely related to Archaea?
    A. Domain Bacteria
    B. Domain Eukarya
    B. Domain Eukarya
  3. What are the similarities between Archaea and Eukarya?
    Hint: There are 3 similarities
    • Share some of the same ribosomal proteins (not found in bacteria)
    • initiate transcription in the same manner
    • have similar types of tRNA
  4. What is the plasma membrane of an archaea cell made up of?
    Contains glycerol linked to BRANCHED-CHAIN hydrocarbons
  5. What is the difference between the plasma membrane of an archaea and a bacteria?
    • Bacteria's plasma membrane: glycerol linked to fatty acids (no branches!)
    • Archaea's plasma membrane: glycerol linked to branched chain hydrocarbons
  6. The cell wall of an archaea are made up of _____________.
  7. What is the difference between the cell wall of an archaea and a bacteria?
    • Bacteria-peptidoglycans
    • Archaea-polysaccharides
  8. All Archaea have a cell wall.
    A. True
    B. False
    • False.
    • Very few do not have a cell wall
  9. What is methanogenesis?
    -The ability to form methane

    **Methanogenesis is a type of metabolism only Archaea can perform!
  10. Some Archaea can be considered photosynthetic.
    A. True
    B. False
    • False!
    • NO ARCHAEA ORGANISM CAN PERFORM PHOTOSYNTHESIS -> (cannot convert solar energy into chemical energy).
  11. Most Archaea are chemoautotrophs.
    A. True
    B. False
  12. Archaea can sometimes be __________.

    • D. A and B only
    • Archaea can be mutualistic or even commensalistic, but NEVER parasitic!
  13. What kind of habitats do methanogens live in ?
    • Found in anaerobic environments
    • swamps, marshes, intestinal tracts of animals

    Methanogens produce methane from Hydrogen Gas, and CO2 coupled to the formation of ATP

    • *Methane (also called biogas) is released into the atmosphere and contributes to the greenhouse effect and global warming.
    • About 65% of the methane found in our atmosphere is produced by these methanogenic archaea.
  14. What kind of habitat are halophiles found in ?
    • Live in High Salt Concentrations. (12-15%[NaCl]) (Seawater is about 3.5%)
    • Found in Great Salt Lake of Utah, Dead Sea.
  15. What type of habitat do thermoacidophiles tlive in ?
    • -extremely hot, acidic environments
    • -Ex: hot springs, geysers, submarine thermal vents, around volcanoes.
    • -They reduce sulfides and survive best in temp above 80 Celsius.
    • -Metabolism of sulfide results in acidic sulfates--grow best at pH 1-2.
Card Set
Biology: Archaea
Biology: Archaea