Time (mins) | Number of living cells in the culture (CFU) 0 | 2,060,000 15 | 2,040,000 30 | 2,060,000 45 | 2,630,000 60 | 4,200,000 90 | 8,400,000 120 | 16,800,000 150 | 35,000,000 210 | 52,000,000 270 | 54,000,000 330 | 54,000,000 390 | 25,700,000 420 | 18,000,000 450 | 6,200,000 Lab Questions: 1. Plot the LOG of the number of living cells in the culture (viable count) using Microsoft Excel. Label the graph with the different phases of growth. (15 Marks) 2. Determine the growth rate and generation time for the particular strain and cultural conditions in our experiment. Remember that the points you need to calculate these values are to be taken from the exponential phase. Show all Lab Questions Continued: 3. The mean division time for a bacterial population is 20 minutes. Calculate how many bacteria will be present after two hours, when starting with 10 bacteria. Show all calculations. (5 marks) 4. If turbidometry readings were also made for the culture described above, draw a labeled diagram to show what the growth curve would look like based on the changes in turbidity with time. Explain the reason for any difference between the growth curve from the viable count and the one for turbidity. (10 Marks) 5. If the culture was producing a valuable product during the stationary phase briefly explain how this phase could be prolonged to get maximum yield of product. (8 Marks)
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To plot the LOG of the number of living cells in the culture using Microsoft Excel, you would first need to create a new column in your spreadsheet and use the LOG function to calculate the log of each cell count. Then, you can use Excel's charting tools to create Show more…
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