SCIENTIFIC METHOD

1
SCIENTIFIC METHOD

• This is a series of steps that scientists use to
  answer questions and solve problems
• Six
• Great
• Farmers
• Plant
• All
• Day

2
Six State the Problem

• Before you start an experiment you must have a
  reason to do it.
• Identify the problem to be solved by answering a
  question
• Problem How do new living things, or
  organisms, come into being?
• You need to be able to test this out in an
  experiment

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Examples of Testable Questions

• Does the amount of sunlight a plant gets affect
  how it grows?
• Does the size of the hole in the bottom of a
  sinking water clock affect how fast it sinks?
• Opinions are not testable questions Examples
• Is Michael Jordan the best athlete of all time?
• Is a dog happy if it wags its tail?

4
Great Gather Information

• The scientist researches the subject that he/she
  is studying.
• Scientist can make observations and draw
  inferences
• Places to do research library, internet,
  encyclopedia, television, etc.

5
Farmers Form Hypothesis (possible explanation)

• For centuries, people believed life came from
  nonliving matter (maggots came from meat)
• Scholars called this spontaneous generation
• This can be considered a hypothesis
• 1668 Francesco Redi (Italian physician) observed
  that maggots appeared on meat a few days after
  flies had appeared.
• He thought flies laid eggs too small to be seen
• His hypothesis therefore was Flies produce
  maggots

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A Well Written Hypothesis

• A well written hypothesis consists of an if
  statement and a then statement.
• The if statement is what your are testing, and
  the then statement is your belief of the
  outcome of the experiment.
• EXAMPLES
• If we increase the size of a hole in the bottom
  of a boat, then the boat will sink at a faster
  rate
• If caffeine is increased in someones body, then
  their reaction time will be quicker

7
Plant Perform Experiment

• Scientists develop a way to test their hypothesis
• Variables factors that can change in an
  experiment (equipment, temp, time)
• Hypothesis tested by experiment where only one
  variable is changed at a time.
• All other variables should be kept unchanged
  (controlled experiment)
• Independent Variable variable that is changed
  (what is being tested)
• Dependent Variable what is the result observed

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• F. Redi designed his experiment
• What was the independent variable (what is being
  tested)?
• Dependent variable (the result)?

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All Analyze Data/Record results

• Scientists compile data into charts and graphs
• This helps make sense of the information taken
  from the experiment
• Redi recorded his data, copies of his work were
  available to later generations of scientists
• Results
• Maggots appeared on meat in uncovered jars.
• Gauze present no maggots

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Day Draw Conclusions

• Scientist decides whether the hypothesis was
  correct or not.
• Redis results supported his hypothesis
• His conclusion Maggots were produced by flies
• Also proved that hypothesis of spontaneous
  generation was not true
• Experiments must be reproducible
• If repeated, result should always be the same
• Scientists communicate results by publishing a
  report in a scientific journal