Question

This mode of movement occurs when bundles of flagella moving counterclockwise become unbundled as some of the flagella switch rotational direction. For 10 points each:
[10m] Name this mode of movement exhibited by peritrichous (“pair-ih-TRICK-us”) bacteria like Listeria monocytogenes and E. coli. During chemotaxis, bacteria suppress this kind of motility in favor of directed runs along concentration gradients.
ANSWER: tumbling [or tumbling motility; or word forms of tumble; accept run-and-tumble motion; accept twiddling motion or word forms of twiddle]
[10h] The concentration of this protein’s phosphorylated form controls the direction of flagellar motion. The histidine kinase CheA (“kee-A”) phosphorylates this protein, which binds FliM to stabilize counterclockwise motion and induce tumbling.
ANSWER: CheY (“kee-Y”) [accept CheY-P]
[10e] Run-and-tumble motion can be modeled as a three-dimensional one of these phenomena biased by the direction of flagellar motion. Diffusion without a chemical gradient is also modeled as this kind of process.
ANSWER: random walk [prompt on random processes or stochastic processes; prompt on walks; prompt on Brownian motion or Wiener processes]

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Data

TeamOpponentPart 1Part 2Part 3Total
Chicago CIllinois A001010
Columbia BWUSTL A001010
Cornell BBrown A001010
Florida AYale B001010
Florida BDuke A001010
Georgia Tech APenn State A1001020
Georgia Tech BClaremont A0000
Harvard AMinnesota A001010
Houston APenn A0000
MIT AMichigan A1001020
Maryland ARutgers A001010
NYU AMinnesota B0000
North Carolina AChicago B1001020
Ohio State AColumbia A1001020
Purdue ASouth Carolina A001010
Stanford ANorthwestern A001010
Texas ARutgers B001010
UC Berkeley AJohns Hopkins A10101030
Virginia AImperial A001010
WUSTL BUC Berkeley B001010
Yale AMcGill A1001020