In an experiment measuring plant height over time, what is the dependent variable?

In an experiment measuring plant height over time, what is the dependent variable?

• A. Time (days)
• B. Plant height (cm)
• C. Amount of water
• D. Temperature

Answer: (B)

The main idea is that the dependent variable is what you measure to see how it changes in response to the factor you control. In a study of plant growth over time, you record how tall the plant becomes as days pass. That height is the outcome you observe and it depends on time (and other conditions you might keep constant or vary). The days themselves are the independent variable—the factor you use to organize measurements. The amount of water and the temperature could influence growth, but they are not the data being collected as the primary outcome in this setup.

The main idea is that the dependent variable is what you measure to see how it changes in response to the factor you control. In a study of plant growth over time, you record how tall the plant becomes as days pass. That height is the outcome you observe and it depends on time (and other conditions you might keep constant or vary). The days themselves are the independent variable—the factor you use to organize measurements. The amount of water and the temperature could influence growth, but they are not the data being collected as the primary outcome in this setup.