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A dichotomous key that distinguishes the five classes of the gram- negative Proteobacteria Answer

A dichotomous key that distinguishes the five classes of the gram- negative Proteobacteria.

  1. a. Anoxygenic photosynthetic bacteria ———————– 2


  1. b. Chemoorganotrophic bacteria ——————————– 4


  1. a. Purple nonsulfer bacteria ———————————– alpha bacteria


  1. a. Purple sulfur bacteria —————————————- 3


  1. a. Oxidize sulfur, sheath forming bacteria, found in sewage, blogs and decomposition areas ———— Beta proteobacteria


  1. b. Oxidize hydrogen sulfide to sulfur and deposit it internally as sulfur granules (usually within invaginated pockets of the plasma membrane); often they eventually oxidize the sulfur to sulfate, largest group of proteobacteria and mostly intracellular pathogenic ————————— Gamma proteobacteria


  1. a. Include predator bacteria that attack other bacteria ———————– Delta proteobacteria


  1. b. Smallest group of proteobacteria, slender gram-negative rods, which can be straight, curved, or helical —————– Epsilon proteobacteria



  1. A dichotomous key that distinguishes the four gram-negative bacteria phyla (i.e. Proteobacteria, Cyanobacteria, Chlorobi, and Chloroflex I)
  2. a. Photoorganotrophic and chemoorganotrophic ——————— Proteobacteria
  3. b. Phototrophic bacteria —————————————————— 2
  4. a. Anaerobic ——————————————————————— 3
  5. b. Aerobic ————————————————————————-4
  6. a. Use hydrogen sulfide, elemental sulfur and hydrogen as electron sources; elemental sulfur produced by sulfide oxidation is deposited outside the cell, obligately anaerobic photolithoautotrophs, non-motile bacteria ——————————————- Chlorobia
  7. b. Can carry out anoxygenic photosynthesis with organic compounds as carbon sources or can grow aerobically as a chemoheterotroph, filamentous, thermophilic, gliding bacteria ———- Chloroflexi
  8. Carry out oxygenic photosynthesis, using water as an electron source for the generation of NADH and NADPH 2, most diverse photosynthetic bacteria group ——————— Cyanobacteria.
  9. A dichotomous key that distinguishes the two gram-positive phyla, Firmicutes and Actinobacteria.
  10. a. High G+ C content—————————- Actinobacteria
  11. b. Low G+C content —————————– Firmicutes
  12. A dichotomous key that distinguishes the remaining bacterial phyla, Planctomycetes, Chlamydiae, Spirochaetes, Bacteroidetes, and Fusobacteria
  13. a. Motile bacteria ————————————-2
  14. b. Nonmotile bacteria —————————— 4
  15. a. Presence of distinctive diderm (double-membrane), and axial flagella (a complex of periplasmic flagella), motile bacteria ————————– Spirochetes.
  16. b. Presence of single membrane, motile or non-motile bacteria ————- 3
  17. a. Obligatory anaerobic, with potent lipopolysachharide and pointed rod ———————– Fusobacteria
  18. a. Obligatory anaerobic, which is mutualistic with mammalian intestine and not pointed rods   —————— Bacteroides.
  19. a. Presence of hold fast, aquatic bacteria found in marine, brackish and fresh water —————- planctomycetes.
  20. b. Absence of hold fast, coexist in an asymptomatic state within specific hosts ——————- Chlamydae.
  21. A dichotomous key that distinguishes the following archaea groupings: Thermophiles, Halophiles, Acidophiles, and Methanogens
  22. a. Archaea group that produce methanogen as metabolic by product ——————————- Methanogen
  23. b. Archaea group that don’t produce methanogen as metabolic by product ———————- 2
  24. a. Archaea that live in high temperature ———————————– Thermophilic
  25. b. Archaea group that live in normal temperature ————————– 3
  26. a. Archaea group that live in low pH ——————————————- Acidophiles
  27. b. Archaea group that live in high pH —————————————- Halophiles



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