How many 1:10 dilutions must you make if you want to go from a thousand-fold dilution to a million-fold dilution? From a thousand-fold dilution to a 100-million-fold dilution? From a million-fold dilution to a billion-fold dilution? Show how you can get to a 10-million-fold serial dilution using just equal dilutions. A dilution series is set up such that the final dilution is a 10-million-fold (10^7) of the original tube. If 100 ul of the 1:10^7 dilution is plated on agar plates and incubated at 37°C, 42 colonies result. Calculate how many CFUs/mL are present in the original bacterial culture. If 200 ul of the 1:10^7 dilution is plated, about how many colonies would you expect to see on a plate after incubation? Calculate how many CFUs/mL are present in the original bacterial culture. If 500 ul of the 1:10^7 dilution is plated, about how many colonies would you expect to see on a plate after incubation? Calculate how many CFUs/mL are present in the original bacterial culture.
Added by Gregory S.
Step 1
Step 1: To go from a thousand-fold dilution to a million-fold dilution, we need to make 3 1:10 dilutions. Show more…
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