The procedure that we followed required irradation of agar plates containing nut
ID: 4846 • Letter: T
Question
The procedure that we followed required irradation of agar plates containing nutrients medium for S. marcescens. This medium contains many different kinds of organic molecules including all 20 amino acids, nucleotides, and coenzymes extracted from milk and from yeast cells. Exposure to UV light could be expected to change the structure of some of theses organic molecules, potentially creating new, toxic molecules that are harmful for S. marcescens. Suggest a way or ways that theses molecules might have affected the outcome of our exercise. How could the exercise be modified to eliminate exposure of the agar medium to UV?Explanation / Answer
Exposure to UV light can create new toxic materials that areharmful for S.marcescens. These molecules can getincorporated into the microorganism and create mutations in theDNA. It can also kill the microorganism.So, if we expose thepetriplates to UV, we may not be able to get a isolated strain ofS.marcescens. The bacteria may become mutated due to theirradiated compounds in the agar. So we cannot isolate the true S.marcescens to studyit. There will be obvious effects like death or mutations whichcannot be seen. Hence, we might think that it is a true strain but it is not atrue one. UV exposure is done for sterilization. So we can simplysterilize the agar medium before streaking the culture on it. Thiscan be done by autoclaving.This prevents any mutations and gives usthe culture of the isolated bacterium--S.marcescens.Related Questions
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