Question

Juan and Hailey heard that spraying vinegar on plant leaves will prevent caterpillars from eating the leaves. They decide to design an experiment to see if this is true. They mark a line down the middle of the garden and then spray the plants on one side of that garden with vinegar. For the next 10 days, they spray the same side of the garden with vinegar and observe how many caterpillars they can count on each side of the line. After 10 days, if there were more caterpillars on the non-vinegar side of the garden than on the side sprayed with vinegar, Juan and Hailey will conclude that vinegar

Answer 1

does prevent caterpillars from eating leaves.

(a) Identify THREE variables that were not specifically controlled in the experimental design.

(b) For each of these variables, describe how they might have affected the outcome of Juan and Hailey’s experiment.

(c) For each of the variables listed, suggest a way to better control them if the experiment were to be repeated.