Scientific Process PPT

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5
L. Coleman 2009
The scientific process: an organized way to solve
problems and find answers to questions about the
natural world.
PURPOSE: Benefit society.
5.
Share what you
learned - PUBLISH
Practical problem, curiosity,
new technology or observation
leads someone to…
1.
Ask a
QUESTION
“YES”?
2.
Form a HYPOTHESIS:
4.
Form a CONCLUSION:
Is hypoth. supported yes, no, partially?
“NO” or “partially”?
Revise one or
both:
predict the answer to
the question
( must be testable)
3.
Do the test
(EXPERIMENT or
make observations
In the field)
a. Use a control
b. Make careful record of data
KNOWLEDGE
of the natural
world.
The Scientific Process starts with developing a…
1. Problem/Question: … that can be solved
through experimentation or observation.
[How, What, When, Who, Which, Why, or Where?]
Example: Why, after rebounding for a few years, is the
population of California sea otters declining again?
Before proceeding to the next step,
make observations and
research your topic of interest.
Do you remember the
next step?
2. Formulate a Hypothesis: Predict
a possible answer to the problem
or question.
Must be testable by experiment or
observation.
Example: Sea otters
are dying from a cat
parasite accumulating
in the ocean as a result
of runoff polluted by cat
feces.
3. Do an experiment or make observations in
nature to test your hypothesis.
• Carefully record
your observations
(data).
• If testing with an
experiment, be sure
you use a control*.
Testing with an experiment.
Testing by
observation.
* A control is the group (or
item) that serves as the
standard of comparison. A
control is the same as the
experimental group(s) in every
way except that the control
receives “no treatment”.
Before going to the next step, organize
and analyze results: (Often includes
graphing and/or mathematical analysis of
data)
TITLE graphs
Pressure change with
temperature increase in a gas
a. Is there a pattern (or
patterns) in the data?
If yes, what does it tell
you about the purpose?
b. Is there evidence that
you may have made
errors?
Label axes include units!
If so, study procedure to
see where errors might
have occurred.
4. Form a Conclusion:
a.
b.
“By golly, I was right!”
Summarize results.
Describe patterns you
identified.
Hypothesize possible
explanation(s) of patterns.
Can you answer purpose
based on your results? If
so, do it! If not, say so and
tell why. Support your
statement with evidence
from data.
Do results support your
hypothesis? If not, identify
possible reason:
c.
d.
e.
–
–
Hypothesis wrong?
Error(s)?
f. Discuss any new questions that
your work raises about the topic.
5. PUBLISH!
• Share what you’ve
learned so others can:
- study your experiment
- repeat it
- pursue questions you
raised.
- and society can
benefit from your work.
• In this class, you share by
writing a lab report!
The body of knowledge of science comes
from many sources:
• Experimental and observational EVIDENCE.
(obtained through the scientific process).
• FACTS: directly observable
phenomena agreed upon by all.
(Example: “ people come in different
heights”).
• LAWS: Statements of fundamental
relationships that always hold true
under specific conditions.
(Example: the Law of Gravity).
THEORY
LAW
FACT
LAW
LAW
Experimental
evidence
LAW
Observational evidence
1. Evidence about a topic from all sources accumulates.
2. Scientists propose and test HYPOTHESES (possible explanations) to
make sense of parts of it.
3. Rarely, someone develops a THEORY: something that explains and is
consistent with every fact, law and bit of evidence on the topic.
In everyday usage a“theory” is a guess. In science it
means just the opposite.THEORIES ARE WHAT
SCIENTISTS ARE MOST SURE ABOUT!
1.
2.
Supported by HUGE bodies of evidence.
If contradictory evidence arises, theory must be
changed to include it.
3. Accurately predict future findings and results.
Three theories organize our understanding of living things:
1. CELL THEORY
2. The “CENTRAL DOGMA”
(How DNA Controls an Organism.)
3. THEORY OF EVOLUTION by
NATURAL SELECTION.
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