Richard Lenski’s ongoing long-term evolution experiment on this organism reached its 73,000th generation in 2020. For 10 points each:
[10e] Name this rod-shaped model organism, a bacteria that thrives in the human gut.
ANSWER: E. coli [or Escherichia coli]
[10h] The original strains in Lenski’s experiment were named based on having one of these structures associated with L-arabinose. A negative feedback loop of attenuation in hairpin loops can repress one of these structures.
ANSWER: operons [accept trp operon; L-arabinose operon or ara operon or araBAD operon]
[10m] One breakthrough in Lenski’s experiment was the ability of E. coli in it to grow in this condition on citric acid. Fermentation can [emphasize] not be conducted under this condition.
ANSWER: aerobic conditions [accept descriptions of oxygen being present; reject “anaerobic”]
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