1. How Scientists Work Section 1-2
Experimenting - Conducting scientific investigations systematically, including identifying and framing the question carefully, forming a hypothesis, managing variables effectively, developing a logical experimental procedure, recording and analyzing data, and presenting conclusions based on investigation and previous research.

2. Designing an Experiment
In this class, you will be asked to analyze the experiments of others, as well as to design and carry out your own experiments.
That makes this section very important!!

3. Designing an Experiment
OBSERVE!!!
Asking a Question
Forming a hypothesis – 2 types:
If (this happens) , then this (these) will be the result(s) , because (scientific explanation based on prior knowledge or experience) .
Null hypothesis: states that there will be NO DIFFERENCE in the two experimental designs.
Setting up a CONTROLLED experiment
Recording and analyzing results
Drawing a conclusion

4. 6. Setting up a CONTROLLED experiment
Variable: a factor in an experiment that can change
Ideally, only ONE variable changes at a time. WHY???
What do we called variables that are not allowed to change?
Controlled variables
Controlled experiment: one in which only one variable is allowed to change (be tested) at a time:
Manipulated variable: AKA, independent variable
Responding variable: AKA, dependent variable

5. Francesco Redi’s Experiment on Spontaneous Generation (1668)

6. John Needham (1745) and Lazzaro Spallanzani’s Tests of Redi’s Findings

7. Louis Pasteur’s (1864) Test of Spontaneous Generation
What other important discoveries are credited to Louis Pasteur?
In each of these instances, Pasteur observed a problem, and sought to design experiments to address the questions asked.

8. Theory
“What’s wrong with my car?” “Well, my theory is……….” What is wrong with this statement?????
Theory: “a well-tested explanation that unifies a broad range of observations”
Could the above statement be correct?
Can a theory be considered the absolute truth?
Law of gravity vs. germ theory of disease

9. Assignment 
Analyzing Data (p.27) ---- Answer in complete sentences!!!!
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