Pre-AP Biology
Ms. Haut
The Process of Science
 The word science is derived from a Latin
verb meaning “to know.”
 Science is a way of knowing.
 Science developed from people’s
curiosity about themselves and the
world around them.
Hypothesis-Driven Science
 As a formal process of inquiry, the
scientific method consists of a series of
steps.
 The key element of the scientific
method is hypothesis-driven science.
Scientific Method
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Observations
Question
Hypothesis
 Prediction
Experiment
Data
Conclusion
Retest
Communicate
Results
Observation

You observe something in the material
world, using your senses or machines
which are basically extensions of those
senses.
AH—Look at this!
Question
You ask a question about what you
observe.
 State the problem or question.
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http://upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Surface_Tension_01.jpg/800px-Surface_Tension_01.jpg
Hypothesis
A testable statement about your
observation
 Based on research
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You should be able to give reasons for why you
chose your hypothesis
If/then… statement
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Deductive reasoning is used in testing
hypotheses
– If a hypothesis is
supported, and we test
it, then we can expect a
particular outcome
• Case study: flashlight
failure
Figure 1.19
Experiment

You figure out a way to test whether the
hypothesis is supported.
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Control group– nothing changed
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Experimental group – one variable changed
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The outcome must be measurable
(quantifiable).
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Record and analyze data.
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Biologists developed a hypothesis
regarding mimicry in snakes.

If an animal has certain color patterns, then
it will not be preyed upon.
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They tested the hypothesis by making
artificial snakes and observing how often
they were attacked by predators.
Figure 1.20
This is an example of a controlled
experiment.
 Such an experiment is designed to
compare an experimental group with a
control group.
 Ideally, a control group and an
experimental group differ in only one
variable.
 Constants: variables that remain the
same in all groups
Figure 1.21
Analyze Results

You do the experiment
using the method you
came up with and
record the results.
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Create data tables,
graphs to represent
data
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Perform calculations
that will determine what
results mean (averages,
percentages, totals)
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Identify possible sources
of errors
Table 1. Percent of total attacks on
different colored artificial snakes.
Draw Conclusions

You state whether
your hypothesis
was supported or
not and try to
explain your
results.
Table 1. Percent of total attacks on
different colored artificial snakes.
Retest

In order to verify the results, experiments
must be retested.
Communicate Results
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Share results with science community
The Culture of Science
Figure 1.22

Scientists build on what has been learned from
earlier research.
 They pay close attention to contemporary scientists
working on the same problem.
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Both cooperation and competition characterize the
scientific culture.
 Scientists check the conclusions of others by
attempting to repeat experiments.
Evolution Connection: Theories in
Science
 What is a scientific theory, and how is it
different from a hypothesis?
 A theory is much broader in scope
than a hypothesis.
 Theories only become widely accepted
in science if they are supported by an
accumulation of extensive and varied
evidence.