16. Microbial Genetics

Which of the following is a major difference between direct and indirect selection of mutants?

A scientist has a population of His+ prototroph and His- auxotroph cells and wants to select and separate the auxotrophs from the prototrophs. Which form of selection should the scientist use?

Replica plating is an example of which type of mutant selection?

What types of bacteria will be growing on the nutrient agar and minimal media at the end of a replica plating experiment?

Why do prototroph bacteria grow on minimal media but auxotroph bacteria do not?

Which of the following colonies of bacteria are composed of His- auxotroph bacteria?

What characteristics are true about the colonies living on the minimal media plate?

After scientists exposed cultures of Penicillium to agents X, Y, and Z, they examined the type and amount of penicillin produced by the altered fungi to find the one that is most effective. Agents X, Y, and Z were probably __________ .

a. recombinant cells

b. competent

c. mutagens

d. phages