The Scientific
Method
Biology – the study of life
 Science – the observation, identification,
description, and explanation of
phenomena (occurrences in the world
around us)
 Latin root for the word science – scientia –
means knowledge

Steps to the Scientific Method
Make an observation
 Ask questions
 Form the hypothesis
 Set up and experiment
 Collect the data
 Draw a conclusion
 Make a prediction
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Scientists believe all natural phenomena in the
universe have logical, verifiable explanations.
 Natural phenomenon – something occurring in
nature that we experience through our senses.
 Scientific process – used to research and
explain natural phenomena

Making Observations and Defining
the Problem
The scientific process begin by observing
and experimenting with the things around
us.
 Observations are made by using the five
senses (sight, smell, touch, sound, and
taste) to obtain information.
 May lead to identifying problems

Asking Questions
Asking appropriate questions is the
second step in solving a problem.
 We are seeking logical explanations
for what we observe and find ways
to solve problems

Forming the Hypothesis
Hypothesis – a statement that gives the
best response to the question and should be
based on already known facts. An educated
guess.
 Can be developed by using inductive
reasoning (the ability of a scientist to draw
from knowledge and experience to make a
general explanation).

Setting Up the Experiment
Scientific Experiment – gives accurate and
measurable results.
 Experiments should be designed to collect
information to prove or disprove the hypothesis.
 An experiment must be set up to examine only
one condition or variable at a time.
 To test the hypothesis, the experiment should
have two components: a control group and one
or more experimental groups.

Control group – the part of the experiment that
is designed without changing any of the
variables
 Experimental group – designed to test
components of the hypothesis and to indicate
changes which might invalidate the hypothesis
 Through observations and measurements of
the different groups, information is collected
and recorded. When data from the control
group is compared to the experimental groups,
the scientist can calculate how much the
variables affected the investigation.

Independent Variable – the factors that are
changed or manipulated during the
experiment. These are the ones an
experiment is trying to test.
 Dependent Variable – Usually the factor that
the experimenter is measuring or counting.
This is the one that changes in response to
the independent variable.
 Control Variable – These are the variables
that you attempt to control. Kept constant.

Collecting Data
Data is gathered from the observations and
measurements taken during a scientific
experiment.
 Observations must be recorded.
 Qualitative data – information that cannot be
assigned a numerical value. (five senses)
 Quantitative data – anything that can be
expressed as a number or can be quantified.
Can be organized in a data table.
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Drawing Conclusions
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Conclusion – judgment or interference based on
observation and experimentation. Drawn from the
results of experiment.
Results – the end product of an experiment.
A scientist must perform an experiment repeatedly to
determine the true outcome of it.
After repeated times of getting the same results, the
hypothesis may become a theory.
Theory – set of related hypotheses that have been
tested and confirmed many times by many scientists.
It unites and explains a broad range of observations.
http://biology.clc.uc.edu/courses/bio104/sci_meth.htm
http://www.biology4kids.com/files/studies_sc
imethod.html