a planned, organized approach to solving a problem Scientific Method a planned, organized approach to solving a problem

1. Define a problem Decide what you want to know Often involves research Put in form of a question

Ex. How are firefly squid affected by below-normal salt levels in sea water?

2. Make a hypothesis Hypothesis – an educated guess to a question that can be answered by an experiment Ex. Death rates of firefly squid will be higher in sea water with below-normal salt levels.

3. Design an experiment a good scientific experiment only tests one variable variables are the factors that change in an experiment

Independent variable – variable that is changed by experimenter ex. Salt levels Dependent variable – variable that changes if the independent variable is changed Ex. Squid death rates

Constants – factors that do not change in the experiment Ex. Water temperature Control – test group used to show that experimental results are due to the condition being tested Ex. Group in normal sea water

4. Gather Data Make observations of what is happening in the experiment Record the observations Collect as much as possible

5. Analyze results Organize the results in graphs, tables and charts Look for trends or patterns Compare the data with the hypothesis

6. Make a conclusion May need to change the hypothesis to fit the results Were there any problems that might have given bad results?

7. Repeat Multiple trials are necessary to prove results are valid Others should also be able to reproduce your results