Name:___________________________ SC/BPHS2090 Final Exam (Lew) Be sure to write your name above. Read the question carefully, think, then write your answer in the lined space (front and back of this page). When finished, please hand your answer in, separate from your exam booklet. QUESTION:The figure below has been modified from a recent publication1in which the authors report on bacterial feeding on nutrient patches in planktonic2habitats in seawater. The diagram on the left (A) shows bacterial tracks surrounding a lysed ciliate3(the ciliate cell is the empty space in the center of the panel). The diagram on the right (B) shows bacterial tracking in a diffuse cloud of nutrient broth. The locations of the bacteria were marked at equal intervals. The duration of the measurements is about 2 seconds; the bars are 50 μm. Explain the difference in the tracking, on the basis of your biophysical knowledge of bacterial motility. KEY:Bacteria search for food by switching between runs and tumbles (5 points). Runs result in a
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