To Map Genes of a Bacterial Strain, Conjugation Must Be

question 20

Multiple Choice

To map genes of a bacterial strain, conjugation must be interrupted at given times. Suppose you have Hfr cells of genotype a+b+c+d+e+strR and F- cells of genotype a- b- c- d- e- strS and you combine these two cultures in liquid medium in four blenders at time 0. After intervals of 3, 6, 9, and 12 minutes, you turn on successive blenders. The resulting cultures were then plated on medium containing streptomycin. Why?

• A) to eliminate non- conjugating Hfr cells
• B) to selectively eliminate cells that have taken in F⁺ genes
• C) to eliminate non- conjugated F^- cells
• D) to eliminate all non- conjugated cells

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Young children from birth to one year of age, focusing on rapid physical and cognitive development during this early life stage.

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