Scientific Method
Dec 31, 2015
• What is the goal of Science?
• Investigate and understand the natural world
• Explain events in the natural world
• Use explanations to make useful predictions
Science as a Way of Knowing• How should you
think about science?• Science is an ongoing process– Involves asking
questions– Observing– Making inferences– Testing hypotheses
• What are the basic components of scientific inquiry?
• 1. Identify the Problem• 2. Formulate testable
Hypothesis• 3. Design & Conduct
experiment• 4. Analyze Data• 5. Develop Conclusion
Let’s Break it Down…..
• 1. Identify the Problem– Make observations using five senses
• Quantitative– Expressed as numbers, counting, or measuring
• Qualitative– Descriptive and involve characteristics that cannot be counted
– Collect information– Develop a question you can test
*A scientist observed maggots “appearing” on raw meat– He wondered how did this happen?*Question for experiment* • What is the cause or source of the maggots on the meat?
Breaking it down …….
• 2. Formulate a testable hypothesis– Could be an If/Then statement– Must relate to independent and dependent
variable
* hypothesis* If I see flies crawling all over the meat, then
flies produce maggots.-OR-Flies produce maggots
• How do we know what the IV and DV are?
variables- 2 kinds
• Independent variable- the factor the experimenter adjusts ( what “I” change)– AKA Manipulated Variable
• Dependant variable- the result (data your collecting)– AKA Responding Variable
Breaking down….• 3. Design and Conduct the experiment
– List materials needed– Make sure it is a valid procedure
• Experiment is not biased (one sided)
– Indentify Variables : IV, DV, constants, control• IV- what “I” change• DV- ‘D’ata you collect• Constants- what needs to stay the same to make the
experiment valid• Control- ‘the original’ unchanged test subject that the IV is
compared to
– Record observations– Collect Data– Multiple trials
Experiment example
• Materials: two jars, meat, gauze, flies, ect…• Control – uncovered meat• Constants - jars, meat, location, temperature,
time• IV- Gauze covering that keeps flies away from
meat• DV - Whether maggots appear or not• Record observations and collect data
– Quantitative & Qualitative• Multiple trials
Breaking it down…
• 4. Analyze Data– Organize data into charts, graphs and tables– Identify if the data supports the hypothesis
*In a lab report you put what you see in your graphs, charts and tables into complete sentences!!!!!!!!
* This shows your understanding of the data gathered
Data tables and Graphing
• CREATING A GRAPH – depends on your variables!– Bar Graph, Line Graph (single or multi –line) or Pie Graphs
• X-axis is the IV (unless multi-line) and Y-axis is the DV• Multi-line graphs have a Key ( which is IV) and time
always goes on x-axis!
Last break down….• 5. Develop Conclusion
– Make clear, concise statement based on results; written as a restatement of the hypothesis
– Accept/reject the hypothesis and explain why– Communicate results– Identify sources of error– Determine the need for further research
*Maggots form only when flies come in contact with meat, so his hypothesis “flies produce maggots” was correct. Spontaneous generation of maggots did not occur.