1. Introduction to Biology
Chapter 1
Scientific Method

2. Scientific Method State the Problem/Question
Gather Information /Educate Yourself
Form a Hypothesis
Perform Experiment
Record and Analyze Data
Form a Conclusion
Repeat the Experiment

3. Designing an Experiment
Start with a question or a problem.
Original question may lead directly to an experiment.
Sometimes the question is too broad to be tested because there are so many possible answers.
The topic may need to be narrowed down.

4. Hypothesis A hypothesis is a proposed scientific explanation for a
set of observations.
Should be written as an “If, Then” statement
If the (Independent Variable) is changed this way, then the (Dependent Variable) will change this way.

5. Designing an Experiment
A carefully designed experiment can test a prediction in a reliable way, ruling out other possible explanations. As scientists plan their experimental procedures, they pay particular attention to the factors that must be controlled.

6. Controlling Variables
Variable – a factor that can change
Three kinds of variables
1. Independent (manipulated)
2. Dependent (responding)
3. Constants

7. Independent Variable
This is the variable that the scientist purposely changes.
AKA – the manipulated variable

8. Dependent Variable
The factor that may change because of the independent variable and that scientists want to observe.
AKA – responding variable

9. Forming Operational Definitions
This is an explicit definition of a variable so that any scientist could measure or control the variable in exactly the same way.
Example
The bamboo will be grown in a cool environment.
The bamboo will be grown in a growth chamber at 15 C.

10. Constant Variables Factors that a scientist purposely keeps the same.
Enables researchers to conclude that changes in the dependent variable are due to changes in the independent variable.

11. Control Group
The control group is to serve as a standard of comparison for your experiment.
Usually considered normal conditions.

12. Record and Analyze Data
Recording data must be done in a neat and organized fashion.
Tables and charts should be used.
A visual representation of the data usually helps pick out patterns or trends.
Use graphs or charts

13. Drawing Conclusions Two conclusions you can draw:
My hypothesis was supported….
My hypothesis was not supported
A hypothesis is not proven.
Evidence from the data must be provided to support the conclusion

14. What to do now?
If your hypothesis was supported, the experiment needs to be repeated to get the same results.
If your hypothesis was not supported, the hypothesis should be reworked and the experimental procedure adjusted and the experiment repeated.