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Title: In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. Post by: theborderline on Oct 20, 2014 I know this is really simple I just do not know how to do it. Don't want to ask the teacher how to work these. I just need someone to explain the process.
In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. The corresponding milk sample was diluted 1:1,000. How many bacteria per milliliter does the milk contain? Thanks Title: In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. Post by: Alexx on Oct 20, 2014 But, how much diluted milk did you put on the plate?
Remember that, each colony deprives from a single cell, so this means that, the amount of milk you put on the plate initially had 100 bacteria. In order to answer, we need to know the amount of diluted milk you put on the plate. If for example that amount is 1ml, then the spoiled milk should have 1*1000*100=100000bacteria/ml. (We multiply with 1000 because the milk was diluted, and with 100 because that how many cells the sample initially had) Title: In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. Post by: Alexx on Oct 20, 2014 And of course, by doing that we find the amount of bacteria/ml the milk had before the experiment. Because later, the amount may have changed.
Title: In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. Post by: theborderline on Oct 20, 2014 I copied and pasted the question exactly as it was.. I'm assuming he meant1m l but I don't know
Title: In testing spoiled milk for the presence of bacteria, you count 100 colonies on a TGEA plate. Post by: Alexx on Oct 21, 2014 Hmm, I think this question seems incomplete then. Maybe these plates have a fixed capacity? I don't know much about them though. Anyways, I hope you will find the correct answer.
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