Question

Identify both the independent and dependent variable in each of the following experiments.

a. Guinea pigs are kept at different temperatures for six weeks. Percent weight gain is recorded.
Independent variable:
Dependent variable:
b. The diversity of snail species is calculated for a coastal area before and after an oil spill.
Independent variable:
Dependent variable:
c. Batches of seeds are soaked in salt solutions of different concentrations. The number of germinated seeds is counted for each batch.

Answer 1

In the experiments, the independent variables are the temperature, the occurrence of the oil spill, and the salt concentration of solutions, while the dependent variables are the percent weight gain of guinea pigs, the diversity of snail species, and the number of germinated seeds respectively.

Step-by-step explanation:

An experiment is a scientific procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact. In an experiment, the independent variable is the one that is changed or controlled by the scientist to observe its effects on the dependent variable, which is what is being measured or tested.

Identifying Variables in Given Scenarios

• a. Independent variable: Temperature at which guinea pigs are kept. Dependent variable: Percent weight gain of guinea pigs.
• b. Independent variable: The occurrence of the oil spill. Dependent variable: The diversity of snail species in the coastal area.
• c. Independent variable: Salt concentration of solution used to soak seeds. Dependent variable: Number of seeds that germinated.

For each scenario, the independent variable is what the researcher changes or manipulates, while the dependent variable is the response that is measured. Other factors that might affect the outcome, known as control variables, are kept constant.