Answered: A stock culture of S. aureus was… | bartleby

Basic Clinical Laboratory Techniques 6E

Basic Clinical Laboratory Techniques 6E

6th Edition

ISBN:9781133893943

Author:ESTRIDGE

Publisher:ESTRIDGE

Chapter7: Basic Clinical Microbiology

Section7.4: The Gram Stain

Problem 5RQ

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A stock culture of S. aureus was serially diluted up to 10'you spread plate 0.1ml in the
two nutrient agar Petri dishes and obtained 20 and 40 colonies, respectively. After 24
hours, the stock culture of S. aureus was serially diluted again up to 10 and 0.Iml was
spread plated to the two Petri dishes and obtained 100 and 150 colonies, respectively
a. That is the cfu/ml in the initial population of S. aureus
b. What is the cfu/ml after 24 hours
c. What is the generation time?

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