A researcher is culturing several different strains of bacteria in the same petri dish. One day, he finds that all of the strains have died off except one. He continues to grow his bacteria for several weeks, and new strains develop. However, after a month he again notices that all but one of his bacterial strains have died off. This is an example of _____ selection.
A)acyclic
B)continuous
C)artificial
D)nonperiodic
E)periodic

Question

Quizplus · Accepted Answer

This is an example of periodic selection because the bacterial strains alternately die off and reappear over time.

A Researcher Is Culturing Several Different Strains of Bacteria in the Same