Scientific Method

1
Scientific Method

• Biology

Image from http//www.synergizedsolutions.com/sim
psons/pictures/bart/scientist.gif
2
What is Science?

• Science
• Is guided by the natural world.
• must explain what is observed with reference to
  nature using biological, physical or chemical
  laws.
• is testable.
• has conclusions that are tentative (can change)
  pending additional information.
• Is potentially falsified e.g., T-rex is a fierce
  predator
• Is one way of knowing about our world.

3
Ways of Knowing

• Experience

Religion
Intuition
Science
4
The Scientific Way of Knowing

• Allow us to gather observable valid data about
  events that occur in the natural world.
• How do we acquire knowledge?
• Observation, investigations, analysis, and
  conclusion
• How do we validate?
• Public, objective, consistent, observable,
  natural, predictable, testable, tentative

5
A Few Important Definitions

• Scientific Hypothesis A testable statement
  about the natural world (it is NOT an educated
  guess)
• A proposed answer to a question.
• Example Plants need water to grow.

6

• Scientific Law A statement that summarizes a
  pattern found in nature.
• Does not attempt to explain it.
• Example Newtons Three Laws of Motion

7

• Scientific Theory A well-substantiated
  explanation of some aspect of the natural world
  (that can incorporate scientific facts, laws,
  inferences, and tested hypotheses)
• Example cell theory, heliocentric theory, plate
  tectonic theory, gravitational theory,
  evolutionary theory, etc.

8

• Scientific Model Makes it easier to understand
  things that are too difficult to observe
  directly.
• Example Atomic Model, Globe, Solar System Model

9
What are the Rules for Scientific Theories?

• A statement that attempts to describe and explain
  a natural phenomenon.
• Must be testable
• Must have predictive power
• Cannot appeal to supernatural agents
• Has been tested over and over and over again.
  Usually not refuted Just make minor changes.

10
ACTION ITEM

• 1. Read about the following terms in your book
  USING JIGSAW
• Hypothesis
• Model
• Law
• Theory
• 2. Complete the foldable for these terms.

11
What is the Scientific Method?

• A structured way of investigating and evaluating
  theories.
• What are the steps?
• Observation
• Information
• Hypothesis
• Experiment
• Results
• Conclusion

12
Observation

• Experience a phenomenon that leads to a question

13
Information

• Gather background information to form an educated
  hypothesis

14
Hypothesis

• Putting your question into a testable format.

15
Experiment

• Design, setup and conduct a test to accept or
  reject the hypothesis

16
Results

• Collect and analyze the data (typically complete
  statistical analysis)

17
Conclusion

• Interpret data, summarize results, accept or
  reject hypothesis, and consider ideas for future
  research.

18
The Cycle
19
New Model of Investigation
20
Experimental Design

• Variables
• Controls
• T-Test
• Statistical Significance
• Validity