Science Words: Hypothesis, Variable, Data, Conclude

Recognize the core vocabulary of scientific investigation at a glance.

Science articles and lab reports use a shared set of terms. A hypothesis is a testable prediction or proposed explanation, often written as an if-then statement. A variable is something that can change in an experiment. The independent variable is what the scientist changes on purpose; the dependent variable is what is measured to see the effect; controlled variables are kept the same so the test is fair.

Data are the recorded results, numbers or observations (data is technically plural, though many people treat it as singular). To conclude is to decide what the data show. Read this example: 'If plants get more light, then they will grow taller. Students gave three groups of plants 2, 6, and 10 hours of light, kept the water the same, and measured height for two weeks. ' Hypothesis: the if-then. Independent variable: hours of light. Dependent: height. Controlled: water.

Recognizing these words lets you read any experiment.

• 1A hypothesis is a testable prediction.
• 2Independent variable: changed. Dependent variable: measured.
• 3Data are results; a conclusion explains what they show.