Micro Diversity Final Exam Flashcards

Obligatory anaerobic process and energetically costly processes occur
in which kind of organisms?

Nitrogen Fixers

Firmicutes, Chloroflexi, Chlorobi, Spirochaete, Proteobacteria are a
part of what type a nitrogen fixers?


What genera are aerobic facultative nitrogen fixers placed in?

Azotobacter, Azospirillum, Beijerinckia

Which free living aerobe grow in carbohydrates, alcohols, and organic acids?


This organism has very large capsules and consume the highest rate of
oxygen of any organism known.


These organisms are obligate anaerobes that lack electron transport systems


Which organism is responsible for most nitrogen fixation in soil?

Clostridium pasterianum

Nitrogen fixing bacteria can form what kind of relationship with
plants, animals and fungi?


An example of a bacteria that is nodule forming.


Explain the symbiotic relationship between Rhizobium and leguminous plants.

Rhizobium cannot fix nitrogen alone
Cells need small amounts of oxygen to generate energy
Both plant and bacteria produce leghemoglobin to maintain low oxygen levels
Heme is produced by the bacteria, globulin is produced by the plants`

What occurs when a root hair has been infected with Rhizobium?

An infection thread invades plant cells and migrates toward root
cells and a root nodule bacteroid is formed

Which enzymes are responsible for reduction of nitrogen?

Dinitrogenase and dinitrogenase reductase

Anaerobic that couples reduction of oxidized metals to grow and uses
insoluble solids (Fe or Mn) as electron acceptors


Gram negative cell that has outer membrane cytochromes that transfer
eletrons into metals