When Lederberg and Tatum performed their experiments on gene transfer in bacteria that lead to our understanding of conjugation,what were their controls?

Question

Quizplus · Accepted Answer

Plating strain A and strain B separately onto minimal media plates to screen for spontaneous prototrophs served as a control to ensure that any prototrophic colonies that grew on the mixed plates were the result of gene transfer via conjugation, rather than spontaneous mutations.

When Lederberg and Tatum Performed Their Experiments on Gene Transfer