Question

Example: Scientists have observed that an antibiotic drug, BAC-X, isn’t working as well as it once did to control infections caused by a bacterium, Nastybacterium destructus. They think the bacteria are evolving increased resistance over time, especially in patients who take a lower dose of the drug.Experiment: 20 cultures of bacteria are grown in plain broth, 20 with a low dose of BAC-X addedAfter 7 days under these conditions, all cultures of the bacteria are tested for sensitivity to BAC-X.Result: bacteria grown in pure medium are controlled by a low BAC-X dose. Those from the BAC-X medium are more resistant; it takes a higher dose of BAC-X to kill them reliably.Independent variable:Dependent variable(s):xExperimental group:Control group:

Answer 1

Independent variable: dosis of the antibiotic or no antibiotic

Dependent variable: sensitivity to BAC-X

Experimental group: cultures of bacteria

Control group: cultures of bacteria grown in a plain broth