Question:
As part of an experiment, Riley planted six plants in regular potting soil. Six other plants were planted in potting soil with coffee grounds. The plants with the coffee grounds are the group. The plants with just potting soil are the group.
As part of an experiment, Riley planted six plants in regular potting soil. Six other plants were planted in potting soil with coffee grounds. The plants with the coffee grounds are the__experimental__ group. The plants with just potting soil are the__control_ group.
Explanation:
During an experiment, data from an experimental group is compared with the data from a control group. Both groups are selected from the same pool or population, so they are identical in all aspects except for the independent variables.
The control group is used to identify any other factors influencing the results obtained in the study, apart from the modified variables of the treatment.
The experimental group is the one that receives the experimental procedure or treatment. The researcher voluntarily changes the independent variables in the experimental group to observe how they affect the group under study. These variables are kept constant in the control group, not influencing the results, while the experimental group receives the treatment. There can be several experimental groups.
In the exposed example, the coffee in the soil is acting as the treatment. And the regular soil is the unchanged environment.
Plants that grow in soil with coffee are the experimental group because the researcher wants to know how the coffee affects the plants´ growth.
Plants growing the regular soil are the control group because they are not affected by the coffee. If there is any other factor influencing the results in the regular soil, it will be revealed by these plants.