Reference no: EM132388990

1) You wish to determine the number of E. coli cells in a 1 mL sample. After generating a 100,000X diluted 1 mL sample, spreading 100 μL of the diluted sample onto a plate, and growing overnight at 37°C, you observe roughly 100 distinct colonies the next day. Assuming a plating efficiency of 100%, roughly how many cells did you have in the original undiluted 1 mL sample?

2) Find the final dilution factor of analyte A going to analyte B after the following sequence of dilutions is performed:

1. 1 mL of analyte A into 9 mL of H₂O = dilution 1 (D1)
2. 2 mL of D1 into 8 mL of H₂O = dilution 2 (D2)
3. 20 μL of D2 into 980 μL of H₂O = analyte B