The table below summarizes the results of a replica-plating experiment where a mixture of 347 E.coli strains of different genotypes were tested for their ability to grow on a variety of media. $\begin{array}{|l|c|}\hline\text { Medium}&\text { Number of colonies that grew}\\\hline\text { complete medium (contains all amino acids, vitamins, } & \\\text { and a variety of carbon sources) } & 347 \\\hline \text { minimal medium (glucose as a carbon source) } & 261 \\\hline \text { minimal medium + ampicillin (an antibiotic) } & 51 \\\hline \text { minimal medium + methionine (an amino acid) } & 303 \\\hline \text { minimal medium + arginine (an amino acid) } & 301 \\\hline \text { minimal medium + methionine + ampicilin } & 57 \\\hline \text { minimal medium + arginine + ampicilin } & 64\\\hline\end{array}$
Based on the data presented above,how many colonies are wild type (met⁺ arg⁺Amp^S) ?

Question

The table below summarizes the results of a replica-plating experiment where a mixture of 347 E.coli strains of different genotypes were tested for their ability to grow on a variety of media.

\begin{array}{|l|c|}\hline\text { Medium}&\text { Number of colonies that grew}\\\hline\text { complete medium (contains all amino acids, vitamins, } & \\\text { and a variety of carbon sources) } & 347 \\\hline \text { minimal medium (glucose as a carbon source) } & 261 \\\hline \text { minimal medium + ampicillin (an antibiotic) } & 51 \\\hline \text { minimal medium + methionine (an amino acid) } & 303 \\\hline \text { minimal medium + arginine (an amino acid) } & 301 \\\hline \text { minimal medium + methionine + ampicilin } & 57 \\\hline \text { minimal medium + arginine + ampicilin } & 64\\\hline\end{array}

Based on the data presented above,how many colonies are wild type (met⁺ arg⁺Amp^S) ?

Quizplus · Accepted Answer

Wild type colonies can grow on minimal medium without any supplements and are sensitive to ampicillin. Therefore, the number of wild type colonies is the number that grew on minimal medium (261) minus those that grew on minimal medium with ampicillin (51), which is 210.

The Table Below Summarizes the Results of a Replica-Plating Experiment