AP BIOLOGY

Detailed explanation-1: -A constant variable, sometimes known as a control variable, is something you keep the same during an experiment.

Detailed explanation-2: -A controlled variable is something that is kept the same in an experiment.

Detailed explanation-3: -In order for a scientist to ensure that only the independent variable is affecting the dependent variable, all the other factors acting upon the test situation (or test subjects) must be kept constant. These factors that must be kept the same are called the controlled variables, or constant variables.