A bacterial culture was grown for 12 hours. At 4-hour interval, the culture was sampled to determine the population of the culture, by transferring 25 ml of the suspension to 225 ml 0.90% NaCl. Three consecutive dilutions were further made by using I ml aliquot in 9 ml of 0.90% NaCl. One ml from each dilution was plated in each of duplicate plates. The following table shows the results of the plating method. 田 Sampling COUNTS 1st dilution 54; 61 2nd dilution 3rd dilution 4h dilution 1st 3; 7 0; 0 0,0 2nd TNTC TNCT 242: 233 28: 37 3rd TNTC TNTC INTC 249-246 * TNTC = Too numerous to count i. Illustrate the dilution series used and label the final dilution of each dilution. ii. Determine the bacterial count (CFU/ml) every 4 hours of incubation for 12 hours. Show all computations.

A bacterial culture was grown for 12 hours. At 4-hour interval, the culture was sampled to determine the population of the culture, by transferring 25 ml of the suspension to 225 ml 0.90% NaCl. Three consecutive dilutions were further made by using I ml aliquot in 9 ml of 0.90% NaCl. One ml from each dilution was plated in each of duplicate plates. The following table shows the results of the plating method. 田 Sampling COUNTS 1st dilution 54; 61 2nd dilution 3rd dilution 4h dilution 1st 3; 7 0; 0 0,0 2nd TNTC TNCT 242: 233 28: 37 3rd TNTC TNTC INTC 249-246 * TNTC = Too numerous to count i. Illustrate the dilution series used and label the final dilution of each dilution. ii. Determine the bacterial count (CFU/ml) every 4 hours of incubation for 12 hours. Show all computations.

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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