Question

Current Attempt in Progress A serial dilution of an E.coli culture was performed, and 1 ml of various dilutions was plated onto nutrient agar. The resulting data are shown in the table below. What is the estimated concentration of cells/ml in the original broth culture? Dilution Vol of inoculum # of colonies 10-6 1.0 ml Too many to count 107 10 ml 270 10 1.0 ml 31 10 1.0 ml Too few to count 31 cells/ml. 2.7 x 107 cells/ml. 3.1 x 10 cells/ml 2.9 x 10' cells/mi.

Answer 1

The estimated concentration of cells/ml in the original broth culture is 5 million cells/mL.

Step-by-step explanation:

The estimated concentration of cells/ml in the original broth culture can be calculated by using the dilution factor and the number of colonies counted on the plates. In this case, the dilution factor is 10,000. From the 1:10,000 dilution, an average of 50 colonies was counted on the plates. Multiplying the number of colonies by the dilution factor gives us the estimated concentration of 5 million cells/mL in the original broth culture.