The "One Step Growth Curve"

Calculate the titre of your phage samples:

Sample: 10-1 10-2 10-3 10-4 10-5 10-6
Free p.f.u: Confluent phage plaques Too many plaques to count (~800) 83 plaques 8 plaques No plaques No plaques
Total p.f.u: Confluent phage plaques Too many plaques to count (~800) 85 plaques 8 plaques No plaques No plaques

Express your answer in terms of 'plaque forming units (pfu)/ml'
(i.e. number of plaques x dilution factor x 10).

Click on the correct answer below:

  1. FREE: 1.6 x 105 p.f.u. ml-1
    TOTAL: 1.7 x 105 p.f.u. ml-1

  2. FREE: 8.3 x 103 p.f.u. ml-1
    TOTAL: 8.5 x 103 p.f.u. ml-1

  3. FREE: 8.3 x 103 p.f.u. ml-1
    TOTAL: 8.5 x 104 p.f.u. ml-1

  4. FREE: 8.3 x 105 p.f.u. ml-1
    TOTAL: 8.5 x 105 p.f.u. ml-1

  5. FREE: 8.3 x 105 p.f.u. ml-1
    TOTAL: 8.5 x 106 p.f.u. ml-1

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