The Scientific Method Learning Goals 1, 3, & 4

The Scientific Method Using the physical, observable world to explain the physical components of nature Biology is done in one of two ways: Discovery Science: describing nature Observations of facts Measurements of phenomena (observable fact) Hypothesis-Based Science: explaining nature Comparative questions Hypotheses Experiments

Types of Biology Write an example of discovery science. Write an example of hypothesis-based science.

Hypothesis-Based Method Observe Question Hypothesize Test/Experiment Conclusion

Additional Resources Bozeman Biology Scientific Method Podcast: http://www.youtube.com/watch?v=GKGtkzgKfkc

1) Observation Begin by observing a problem in nature A problem can be anything you don’t know how to explain Observations can be of everyday life, nature, space, etc. The physical world/universe

2) Question The question/problem must be: Correct Example: Specific Comparative Testable Correct Example: Will Tylenol tablets reduce pain faster than Advil tablets? Incorrect Example: Is the Mona Lisa more beautiful than The Blue Boy?

Write a Comparative Question We will be testing how quickly antacids dissolve in different water samples. Write a comparative question for the above experiment that you can test.

3) Hypotheses A possible outcome in an experiment Example: Your prediction of what will happen. Example: Antacids will dissolve more quickly in lemonade than orange juice.

Hypotheses Practice Write a hypothesis for your antacid experiment

4) Test/Experiment Must address your question Must be repeatable 2 groups (one for each part of your comparison): Independent variable – the 1 difference between the 2 groups The scientist intentionally adds or removes something from one group; this is recorded as data Dependent variable – changes that occur during the experiment As a result of the independent variable This is recorded as data Controlled Experiment/Variables – everything else in the experiment must remain the same between both groups

Tests What is the independent variable in your antacid experiment? What is the dependent variable you expect to record in your antacid experiment?

Experimental Error The study of life can be difficult, mistakes will happen: Avoidable error An error that can be controlled for in future experiments Unavoidable error An error that cannot be corrected for

There are many sources of error (next to each type put whether they are avoidable or unavoidable) Not following instructions = _______ Disease = _______ Measuring mistakes = _______ unpredictable animal behavior = _______ Death = _______ human error = _______

5) Conclusion An analysis of the data collected during the experiment Explanation of what happened Explain the results and compare them to your hypotheses Build on ideas that succeed; reject ideas that fail Scientists will often publish their success to share with the world, and to make sure they get credit for their discovery A theory is a strong scientific statement supported by hundreds of experiments

Mythbusters Did they do the science the correct way? http://www.youtube.com/watch?v=Tmut9NOtvnY Identify: Observation, question, hypotheses, experiment, independent variable, dependent variable, & conclusions What could they have done better?