Variable

Definition

A variable is any factor, trait, or condition that can exist in differing amounts or types within an experiment. In biology, variables are crucial for testing hypotheses and observing outcomes.

5 Must Know Facts For Your Next Test

1. A variable can be independent or dependent, where the independent variable is manipulated to observe its effect on the dependent variable.
2. Control variables are kept constant to ensure that the results of an experiment are due to the manipulation of the independent variable.
3. In a well-designed experiment, only one independent variable should be tested at a time to establish a clear cause-and-effect relationship.
4. Variables must be measurable and clearly defined to produce reliable and reproducible results.
5. Biologists use variables to conduct experiments that help them understand biological processes and validate their hypotheses.

Review Questions

• What is the difference between an independent variable and a dependent variable?
• Why are control variables important in an experimental setup?
• How does manipulating an independent variable help scientists test their hypotheses?

Related terms

Hypothesis: A proposed explanation for a phenomenon that can be tested through experimentation.

Control Group: The group in an experiment that does not receive the experimental treatment, used as a benchmark to measure how the other tested subjects do.

Data: Information collected during an experiment, which can be quantitative (numerical) or qualitative (descriptive).