1. A bacterial culture was grown for 12 hours. At 4-hour interval, the culture was sampled to determine the population ofthe culture, by transferring 25 mlof the suspension to 225 ml 0.90% NaCl. Three consecutive dilutions were further made by using 1 mlaliquot in 9 mlof 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. EDI Sampling COUNTS 1st dilution 54; 61 TNTC 2nd dilution 3; 7 TNCT TNTC 3rd dilution 0; 0 242; 233 TNTC 4th dilution 0, 0 28: 37 249;246 1st 2nd 3rd TNTC * TNTC = Too numerous to count i. Determine the bacterial count (CFU/ml) every 4 hours of incubation for 12 hours. Show all computations. a. 1s* Sampling b. 2d Sampling c. 3* Sampling

1. A bacterial culture was grown for 12 hours. At 4-hour interval, the culture was sampled to determine the population ofthe culture, by transferring 25 mlof the suspension to 225 ml 0.90% NaCl. Three consecutive dilutions were further made by using 1 mlaliquot in 9 mlof 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. EDI Sampling COUNTS 1st dilution 54; 61 TNTC 2nd dilution 3; 7 TNCT TNTC 3rd dilution 0; 0 242; 233 TNTC 4th dilution 0, 0 28: 37 249;246 1st 2nd 3rd TNTC * TNTC = Too numerous to count i. Determine the bacterial count (CFU/ml) every 4 hours of incubation for 12 hours. Show all computations. a. 1s* Sampling b. 2d Sampling c. 3* Sampling

Basic Clinical Lab Competencies for Respiratory Care: An Integrated Approach

5th Edition

ISBN:9781285244662

Author:White

Publisher:White

Chapter19: Equipment Processing And Surveillance

Section: Chapter Questions

Problem 9SEPT

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