Concept explainers
In a transformation experiment involving a recipient bacterial strain of genotype a–b–, the following results were obtained. What can you conclude about the location of the a and b genes relative to each other?
HINT: This problem involves an understanding of how transformation can be used to determine if bacterial genes are closely “linked.” You are asked to predict the location of two genes relative to one another. The key to its solution is to understand that cotransformation (of two genes) occurs according to the laws of probability. Two “unlinked” genes are transformed only as a result of two independent events. In such a case, the probability of that occurrence is equal to the product of the individual probabilities.
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Concepts of Genetics (12th Edition)
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