1. Scientific Method Used to answer a question or solve a problem

2. Scientific Method Steps (or what you have been told up to now) Step 1: OBSERVE Step 2: ASK A QUESTION Step 4: MAKE A HYPOTHESIS Step 3: RESEARCH Step 5: TEST HYPOTHESIS Step 6: CONCLUSION

4. For a PhD student  Needed to form a hypothesis  Look up everything that is already known. Read papers published in journals/books /scientific literature For a High school student  Need to understand currently discussed material  Understand the purpose of the lab activity Background Research

5. A Controlled Experiment or lab activity includes: Testable hypothesis Variables A Control Planned steps Test one variable at a time

6. Variables Independent (manipulated) variables:  What is being tested  the variable that can be changed  May cause a change in the dependent variable Dependent (responding) variables:  The factor that is being measured or observed  The data  May change because of the independent variable Controlled variable (constant):  Stays the same  Controlled by experimenter  Are potential independent variables in future experiments

7. Creating a hypothesis in high school A Hypothesis will help us understand how the independent variable will affect the dependent variable Example: Typically start with a question: How does the amount of salt affect the growth of a seed? IV: amount of salt DV: growth of a seed CV: everything that doesn’t change. Amount of water, type of plant so on.

8. Hypothesis and it’s many definitions A possible solution to the question/problem. A statement that can be tested by conducting an experiment Prior knowledge, new information, observations can be used to form a hypothesis Like a prediction but it involves variables  How will the independent variable affect the dependent variable Is stated as a IF,THEN statement  IF the independent variable is changed by you, THEN predict how the dependent variable will respond. Example: If the plant is given an increased amount of salt water, then the plants growth will decrease.

9. EXAMPLE Background: Red Bull ads claim to increase concentration Ques: Can Drinking Red Bull before a test improve performance ? Identify variables (anything that changes):  Independent variable: red bull drinks  Dependent variable: performance on test  Control variables: time when drink was consumed, other types of stimulants the student has, test environment…. Hypothesis: If red bull drink is consumed 15 minutes before the test then, average test score of students in a Biology class will increase by 5% or more.

10. Experiment- test the hypothesis Experimental Design or lab activities may contain the following: A. Variables (3 types) independent, dependent, and controlled/constant B. Control Group/Setup-does not have the independent variable water with no salt Group without red bull C. Experimental Group/Setup- has the independent variable water with salt group that drinks red bull D. Procedures: detail steps to test experiment. (Test only one variable at a time, but in different quantities or types is ok)

11. Data: Information gathered Qualitative data Descriptive observations- such as color, texture, shape, size, and behavior Using the 5 senses Quanitative data measurements Data Table: A way to record results & observations Have a descriptive title Shows the independent variable Has a place to record dependent variable The more trails conducted, the more likely the results are reliable

12. Analyze Data Graph the data Find averages Look for patterns and relationships

13. Type of errors In science no measurement is exact. Errors will affect our results even when we use a 10 cent ruler or $800 scale. The types of error you will see are:  Human error (another word for mistake!) Not considered experimental error but should still be reported  Random Error (variation that increases or decreases measured data)  Systematic Error (something in the experiment itself causes variation in one direction) (please refer to Experimental error handout for further details) Borrowed from Mr. Thompson, chemistry teacher

14. Conclusions (we will be doing this in class during the year) Sums up the experiment by answering the original questions or restating the concept investigated. States whether or not the hypothesis was supported (it is never “right” or “wrong”)  If it does: the hypothesis is accepted  If not: the hypothesis is rejected Discuss issues or problems with experiment. (see error handout) Discuss the importance or relevance of the experiment or investigated concept Pose questions for further research or state ways you would change the investigation

15. Now it is your turn! Taking the lab activity we did in class previously, find the things that match or do not match to what was just discussed here. Be sure to identify the following, we will go over when you are finished;  Independent variable  Dependent variable  Constant variable  Hypothesis  Control Group/Setup and Experimental Group  Errors and what types

16. Answers for your turn Independent Variable: Antibiotics Dependent Variable: bacteria growth Constant variable: amount of water on agar, time to grow, nutrients in agar, etc. Hypothesis: If antibiotics are added to agar in different concentrations, then the growth of bacteria will change. (Very simple form variations will exist) Control group: R2A agar with no antibiotics Errors will vary