In a nutrient medium that lacks histidine, a thin layer of agar containing around 10^9 Salmonella typhimurium histidine auxotroph produces around 13 colonies over a two day incubation period at 37 degrees centigrade. How do these colonies arise in the absence of histidine? The experiment is repeated in the presence of 0.4 micrograms of 2-aminoanthracene. The number of colonies the number of colonies produced over 2 days exceeds 10,000. What does this indicate about 2- anthracene? what can you surmise about its carcinogenicity?
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In a nutrient medium that lacks histidine, a thin layer of agar containing around 10^9 Salmonella ty...
Mathematics, 21.09.2019 01:30