Science Common Sense

476 - What is the role of a control group in an experiment?

In a science experiment, a control group is a group of people or things that don't get the treatment or change being tested. This group stays the same, or "normal", without any changes.

The control group helps the scientist compare the results of the group that gets the treatment to the group that doesn't. It shows how things normally happen, and then the scientist can see if the treatment really made a difference.

For example, let's say you're testing whether a new fertilizer makes plants grow faster. You would have one group of plants with the fertilizer (the test group) and one group without (the control group). By comparing the growth of the two groups, you can see if the fertilizer really works.