1.- As a researcher, you are charged with determining the side effects of a new drug. From previous observations, you suspect that this drug reduces the rate of DNA production (replication) within skin cells of patients using the drug. With the following materials, design an experiment that would answer your questions about the effect of the drug on DNA production. You know that: DNA contains phosphate groups. You have: radioactive isotopes of phosphate (32P), skin cell cultures from various patients, the drug in question, and a device that measures radioactivity.

2.- During an experiment, what is the purpose of a control group?

3.- In the experimental evaluation of a new drug, what is the purpose of a placebo?

4.- Please explain the Scientific Method Steps.