What Do Scientists Do? SWBAT List and describe the steps of the scientific method; Differentiate between problems that would be best solved by an experiment and those that would be best solved by a survey; List three characteristics of a problem that can be solved using the scientific method; Describe several ways in which the scientific method is subject to error

Scientific Method An organized way of arriving at a workable solution to a problem. An organized way of arriving at a workable solution to a problem. –Not a rigid step by step approach, but it is generally followed

Scientific Method Step 1: Establish the problem or questions Step 1: Establish the problem or questions 1. Must be observable 2. Must be measurable 3. Must be repeatable Step 2: Background research Step 2: Background research –What can you find out? –Has anyone already answered the question? –Experimenting without research is wasteful and costly

Scientific Method Step 3: Form a hypothesis Step 3: Form a hypothesis –An educated guess –Based on observation and research Step 4: Experiment: Test the hypothesis Step 4: Experiment: Test the hypothesis –Data – information –Experiment – person tries to control the factors of two or more groups –Experimental variable – the factor that changes in and experiment –Experimental group – group that experiences the experimental variable –Control – lacks the experimental variable

Scientific Method Step 5: Analyze the data Step 5: Analyze the data –Classifying – arranging data so that relationships can be seen Charts Charts Graphs Graphs Step 6: Conclusion Step 6: Conclusion –Verified answer – an answer a person solving the problem is confident is correct

Conquering Pellagra Doctors believed pellagra was spread by germs Doctors believed pellagra was spread by germs –Hypothesis No one know what caused it or how to cure it No one know what caused it or how to cure it –Problem Goldberger observed pellagra victims Goldberger observed pellagra victims –Research Goldberger researched in the south Goldberger researched in the south –Research

Conquering Pellagra Goldberger noted and unusual condition in an orphanage Goldberger noted and unusual condition in an orphanage –Research The orphans who ate more meat and milk were less likely to get pellagra. The orphans who ate more meat and milk were less likely to get pellagra. –Research Goldberger began to believe poor diet led to pellagra Goldberger began to believe poor diet led to pellagra –Hypothesis

Conquering Pellagra Goldberger devised and experiment to test the second half of his hypothesis Goldberger devised and experiment to test the second half of his hypothesis –Experiment Six months later no child had pellagra Six months later no child had pellagra –Data He tried again at an asylum in Georgia He tried again at an asylum in Georgia –Experiment, Verification

Conquering Pellagra Five months after his experiment started the women with better diets didn’t have pellagra Five months after his experiment started the women with better diets didn’t have pellagra –Data The data supported his hypothesis The data supported his hypothesis –Classify and analyze He got volunteers for his second experiment from a prison He got volunteers for his second experiment from a prison –Experiment

Conquering Pellagra The prisoners had their diets changed for six month The prisoners had their diets changed for six month –Verification The men developed tiredness, headaches, stomachaches and dizziness The men developed tiredness, headaches, stomachaches and dizziness –Data Goldberger’s hypothesis was correct Goldberger’s hypothesis was correct –Conclude or choose answer