You are given a 1 gram soil sample of unknown bacterial load. After doing 10-fold serial dilutions of the soil in sterile water, 100 uL volumes are taken from each dilution for preparation of pour plates. Following incubation, each half of the 10-8 plate has 46 colonies.a) What was the dilution factor?b) How many bacteria were present in the soil?2. Staphylococcus aureus divides every 20 minutes. A culture begins with 10 bacterial cells.a) After 5 hours, how many generations have occurredb) After 5 hours, how many bacteria are present?3. How many milliliters would you need to prepare a 10-2 dilution from a 10ml starting culture?

You are given a 1 gram soil sample of unknown bacterial load. After doing 10-fold serial dilutions of the soil in sterile water, 100 uL volumes are taken from each dilution for preparation of pour plates. Following incubation, each half of the 10-8 plate has 46 colonies.a) What was the dilution factor?b) How many bacteria were present in the soil?2. Staphylococcus aureus divides every 20 minutes. A culture begins with 10 bacterial cells.a) After 5 hours, how many generations have occurredb) After 5 hours, how many bacteria are present?3. How many milliliters would you need to prepare a 10-2 dilution from a 10ml starting culture?

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 1UTM: A surgical technologist working in the Central Sterile Processing Department is asked to run the...

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