Transcript ScientificMethod PowerPoint

Chapter 1 Section 2
Science as a Process
Ms. Scerra
Behavior of Natural Systems
The goal of Science is to explain natural
phenomena.
Scientists:
Start with the assumption that nature is
understandable and predictable.
However, natural systems are complex so…
Scientists follow the same basic method of
studying and describing natural events.
1. Ask a Question
 Scientific inquiry begins with observation.
 Science inquiry involves asking questions
and processing information from a variety
of reliable sources.
Observation vs. Inference
Observation- direct way of gathering
information in an organized way.
Inference- taking observations and
making a logical conclusion
Let’s make some observations!
2. Form a Hypothesis
Hypothesis - a testable explanation of a
situation.
Hypothesis that are supported through
experiments and data are then accepted in
the scientific community.
3. Test the Hypothesis
An Experiment - a procedure carried out
by certain guidelines.
Experiment Variables
Independent Variable –
Only one factor in an experiment that you
change. Ex: Amount of Sunlight
Dependent Variable –
What is being tested or measured
Results from or depends on changes to the
independent variable Ex: A Plant Growing
Control Group- group you keep the same
(all variables are constant)
Scientific
Measurements
Precision –
exactness of the
measurement.
Accuracy – how
close a measurement
is to the true value of
the thing being
measured.
Analyzing the Data
A graph of the data makes easier to
interpret.
4. Report Conclusions
Conclusions are reached after
Controlled experiments
Unbiased investigations
Large amounts of data
 Conclusions are published so others can
review the results and discuss the merit of
the experiment.
Finally…..
A Scientific Theory is made.
Theory- explanation of a natural phenomenon
supported by many observations and
experiments over time
A theory is NOT the final answer because
Scientists debate each other ideas
New information can always change a
theory
Identify the following terms: identify the
problem, hypothesis, experiment,
independent variable, dependent variable,
and create a conclusion
The leaves on my tomato plants were
turning yellow. I was not sure what to do.
I decided that maybe they were not getting
enough sun. I moved one plant into the
sun and left the other one where it was.
I recorded the different shades of the
leaves (yellow, yellow-green, and green).