A culture of Staphylococcus of unknown density is diluted as follows (letters represent each step): • 60 mL of a bacterial culture is diluted by adding 440 mL of water • 1000 microliters from (A) is added to 9 mL of water • Dilution (B) is used to prepare a 103 dilution in water • 100 uL from dilution (C) is plated to nutrient agar and incubated at 37°C Following incubation, colonies are uniformly distributed on the agar, and 102 colonies are counted on one half of the plate. 1. Express the total CFU/mL of the original culture in scientific notation. 2. If 10 uL is plated from dilution (C), how many colonies should grow on the plate?

A culture of Staphylococcus of unknown density is diluted as follows (letters represent each step): • 60 mL of a bacterial culture is diluted by adding 440 mL of water • 1000 microliters from (A) is added to 9 mL of water • Dilution (B) is used to prepare a 103 dilution in water • 100 uL from dilution (C) is plated to nutrient agar and incubated at 37°C Following incubation, colonies are uniformly distributed on the agar, and 102 colonies are counted on one half of the plate. 1. Express the total CFU/mL of the original culture in scientific notation. 2. If 10 uL is plated from dilution (C), how many colonies should grow on the plate?

Microbiology for Surgical Technologists (MindTap Course List)

2nd Edition

ISBN:9781111306663

Author:Margaret Rodriguez, Paul Price

Publisher:Margaret Rodriguez, Paul Price

Chapter4: The Prokaryotes

Section: Chapter Questions

Problem 4UTM

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