Cherry Creek is to be sampled for total bacterial counts to determine if it should remain...

  

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Cherry Creek is to be sampled for total bacterial counts to determine if it should remain open to the public. A 100 mL sample of creek water is collected for analysis; 15 mL of sample is added to 88.5 mL sterile water; 30 mL of this is removed and added to 200 mL of sterile water; 0.1 mL of this is added to 99.9 mL of sterile water and 0.1 mL is plated out. After 24 hours at 30°C, 160 colonies were counted. a) What is the original microbial concentration of the Cherry Creek water you sampled? b) How many bacterial cells are in your sample? c) The EPA recommends that Recreational Waters not exceed more than 406 E.coli/100 mL water sampled. If the sample exceeds the given concentration, the recreational waterway should be closed to the public. Why can't your calculated concentration be used as justification to close Cherry Creek to the public due to coliform contamination? Cherry Creek is to be sampled for total bacterial counts to determine if it should remain open to the public. A 100 mL sample of creek water is collected for analysis; 15 mL of sample is added to 88.5 mL sterile water; 30 mL of this is removed and added to 200 mL of sterile water; 0.1 mL of this is added to 99.9 mL of sterile water and 0.1 mL is plated out. After 24 hours at 30°C, 160 colonies were counted. a) What is the original microbial concentration of the Cherry Creek water you sampled? b) How many bacterial cells are in your sample? c) The EPA recommends that Recreational Waters not exceed more than 406 E.coli/100 mL water sampled. If the sample exceeds the given concentration, the recreational waterway should be closed to the public. Why can't your calculated concentration be used as justification to close Cherry Creek to the public due to coliform contamination? Cherry Creek is to be sampled for total bacterial counts to determine if it should remain open to the public. A 100 mL sample of creek water is collected for analysis; 15 mL of sample is added to 88.5 mL sterile water; 30 mL of this is removed and added to 200 mL of sterile water; 0.1 mL of this is added to 99.9 mL of sterile water and 0.1 mL is plated out. After 24 hours at 30°C, 160 colonies were counted. a) What is the original microbial concentration of the Cherry Creek water you sampled? b) How many bacterial cells are in your sample? c) The EPA recommends that Recreational Waters not exceed more than 406 E.coli/100 mL water sampled. If the sample exceeds the given concentration, the recreational waterway should be closed to the public. Why can't your calculated concentration be used as justification to close Cherry Creek to the public due to coliform contamination? Cherry Creek is to be sampled for total bacterial counts to determine if it should remain open to the public. A 100 mL sample of creek water is collected for analysis; 15 mL of sample is added to 88.5 mL sterile water; 30 mL of this is removed and added to 200 mL of sterile water; 0.1 mL of this is added to 99.9 mL of sterile water and 0.1 mL is plated out. After 24 hours at 30°C, 160 colonies were counted. a) What is the original microbial concentration of the Cherry Creek water you sampled? b) How many bacterial cells are in your sample? c) The EPA recommends that Recreational Waters not exceed more than 406 E.coli/100 mL water sampled. If the sample exceeds the given concentration, the recreational waterway should be closed to the public. Why can't your calculated concentration be used as justification to close Cherry Creek to the public due to coliform contamination?

Answer rating: 100% (QA)

a Original microbial concentration We cant directly calculate the original concentration from the information provided The dilutions performed reduce ... View the full answer