Scientists want to determine whether chemical X, a component of fertilizer, is harmful to fish. They treat fish in the laboratory with increasing amounts of the chemical for one week and then measure their viability. Fish that are not treated with chemical X are considered ____.
A) experimental data
B) controls
C) replicates
D) experimental variables
E) the null hypothesis

Question

Scientists want to determine whether chemical X, a component of fertilizer, is harmful to fish. They treat fish in the laboratory with increasing amounts of the chemical for one week and then measure their viability. Fish that are not treated with chemical X are considered ____.
A) experimental data
B) controls
C) replicates
D) experimental variables
E) the null hypothesis

Quizplus · Accepted Answer

Fish that are not treated with chemical X serve as controls in the experiment. Controls are used to provide a baseline to compare the effects of the experimental treatment (in this case, chemical X) against, allowing scientists to determine the impact of the treatment on the experimental subjects.

Scientists Want to Determine Whether Chemical X, a Component of Fertilizer