Scientific Method

Science To investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions.

Scientific Method Hypothesis: an educated explanation to a problem Controlled experiment: an experiment in which only one variable is changed at a time Control: factors kept the same Variable: factors that change Independent variable: factor being physically changed Dependent variable: factor that changes in response to the independent variable; factor being tested Conclusion: was the hypothesis correct

Notable Experiments Redi Pasteur

Redi Spontaneous generation: the idea that life can arise from nonliving matter Hypothesis  flies cause maggots Designed an experiment Had jars with meat, some covered with gauze, others left open Controlled variables: jars, type of meat, location, temperature, time. Independent (manipulated) variable: gauze or no gauze Dependent (responding) variable: whether maggots appear Conclusion: jars with no gauze (no contact with flies) had no maggots, jars with gauze had maggots, therefore spontaneous generation doesn’t exist

Pasteur Used the curved neck flask Conclusion: air can be allowed in, but no microorganisms to inhibit the growth of other microorganisms.