Final answer:
In experiments, the independent variable is controlled by the researcher and the dependent variable is what is measured. In the students' memory study, sleep is the independent variable and memory performance is the dependent variable. In the analysis of liquids on blueberry production, the type of liquid is independent and the berry count is dependent. For CO2 measurement, the year is independent and CO2 levels are dependent.
Step-by-step explanation:
Identifying the independent and dependent variables in an experiment is essential for understanding the cause-and-effect relationship being tested. In the context of scientific experiments:
- The independent variable is the variable that is controlled or manipulated by the researcher to observe its effect on the dependent variable.
- The dependent variable is the variable that is measured or observed, and it is expected to change as a result of manipulations of the independent variable.
In the given scenarios:
- For a study that tests students' memory after different amounts of sleep:
Independent variable: amounts of sleep
Dependent variable: memory performance - For an analysis of the effect of different types of liquids on blueberry bushes' berry production:
Independent variable: type of liquids
Dependent variable: amount of berries produced - For measuring levels of carbon dioxide in the atmosphere each year:
Independent variable: year/time
Dependent variable: levels of carbon dioxide
Knowing which variable is which can help a researcher better design their experiment and understand their results.