Question

Determine the variables tested in each of the following experiments. If applicable, determine and identify any positive or negative controls. A study is being done to test the effects of habitat space on the size of fish populations. Different sized aquariums are set up with six goldfish in each one. Over a period of six months, the fish are fed the same type and amount of food. The aquariums are equally maintained and cleaned throughout the experiment. The temperature of the water is kept constant. At the end of the experiment, the number of surviving fish are surveyed. A. Independent Variable: B. Dependent Variable: C. Controls:

Answer 1

Independent Variable- size of aquariums

Dependent variable - number of surviving fish

Controls: nil

Explanation:

In every experiment, the independent variable is manipulated and its effect on the dependent variable is observed as certain factors are kept constant.

In this study, the independent variable is the size of the aquariums. As this factor is manipulated, the number of surviving fish (dependent variable) changed accordingly. There was no mention of a control group in the experiment.

However, temperature, amount of food and type of food were held constant for all the experimental groups.