\n'); DuckWin.document.write('\n\n'); DuckWin.document.write(' \n');
DuckWin.document.write(' \n'); DuckWin.document.write(' \n');
DuckWin.document.write(' This page contains a Corel Presentations Show
It! Player that your browser was unable to view.\n');
DuckWin.document.write(' \n'); DuckWin.document.write('
\n'); DuckWin.document.write(''); DuckWin.document.close(); }
The Scientific Method
What's going on in this picture? What steps would you follow to figure
out what's happening here?
Click on the correct answer, then click on the right spot on the
picture.
( ) Someone's pet monkey has been chewing on this banana.
( ) Somebody threw their garbage in the birdbath.
( ) This is a butterfly eating fermented banana juice.
(*) This is a moldy banana with a bunch of old, dead leaves.
( ) There is a spider hiding under this banana waiting to catch
hummingbirds. Image Map Here
See pages 6-7, figure 1.5 in your text.
The following steps make up the Scientific Method. These steps make up
a method which may be used to logically solve problems in many other
areas of life.
Observation:
A good scientist is observant and notices thing in the world
around him/herself. (S)he sees, hears, or in some other way
notices what's going on in the world, becomes curious about
what's happening, and raises a question about it.
Hypothesis:
This is a tentative answer to the question: an explanation for
what was observed. The scientist tries to explain what caused
what was observed (hypo = under, beneath; thesis = an
arranging).
+ Hypotheses are possible causes. A generalization based on
inductive reasoning is not a hypothesis. An hypothesis is not
an observation, rather, a tentative explanation for the
observation.
+ Hypotheses reflect past experience with similar questions
("educated propositions" about cause).
+ Multiple hypotheses should be proposed whenever possible. One
should think of alternative causes that could explain the
observation (the correct one may not even be one that was
thought of!)
+ Hypotheses should be testable by experimentation and
deductive reasoning.
+ Hypotheses can be proven wrong/incorrect, but can never be
proven or confirmed with absolute certainty. Someone in the
future with more knowledge may find a case where the
hypothesis is not true.
Prediction:
Next, the experimenter uses deductive reasoning to test the
hypothesis.
+ Inductive reasoning goes from a set of specific observations
to general conclusions: I observed cells in x, y, and z
organisms, therefore all animals have cells.
+ Deductive reasoning flows from general to specific. From
general premises, a scientist would extrapolate to specific
results: if all organisms have cells and humans are
organisms, then humans should have cells. This is a
prediction about a specific case based on the general
premises.
+ Generally, in the scientific method, if a particular
hypothesis/premise is true, then one should expect
(prediction) a certain result. This involves the use of
if-then logic.
Testing:
Then, the scientist performs the experiment to see if the
predicted results are obtained. If the expected results are
obtained, that supports the hypothesis.
In science when testing/doing the experiment, it must be a controlled
experiment. The scientist must contrast an "experimental group" with
a "control group". The two groups are treated EXACTLY alike except for
the ONE variable being tested. Sometimes several experimental groups
may be used. For example, in an experiment to test the effects of day
length on plant flowering, one could compare normal, natural day
length (the control group) to several variations (the experimental
groups).
When doing an experiment, replication is important. Everything should
be tried several times on several subjects. For example, in the
experiment just mentioned, a student scientist would have at least
three plants in the control group and each of the experimental groups,
while a "real" researcher would probably have several dozen. If a
scientist had only one plant in each group, and one of the plants
died, there probably would be no way of determining if the cause of
death was related to the experiment being conducted.
The experimenter gathers actual, quantitative data from the subjects.
For example, it's not enough to say, "I'm going to see how the dog
reacts in this situation." Rather, in that experiment, the scientist
might have a list of certain behaviors, and record how often the dog
exhibits each of those pre-defined behavior patterns. Data for each of
the groups are then averaged and compared statistically. It's not
enough to say that the average for group "X" was one thing and the
average for group "Y" was another, so they were different or not. The
scientist must also calculate the standard deviation or some other
statistical analysis to document that any difference is statistically
significant.
Research is cumulative and progressive. Scientists build on the work
of previous researchers, and one important part of any good research
is to first do a literature review to find out what previous research
has already been done in the field.
_________________________________________________________________
REVIEW THE STEPS IN THE SCIENTIFIC METHOD
Get the Corel Presentations
Show It!™ plug-in [Show It!] Show It! online help
Click the picture to re-start or press [ESC] to stop. You may also
"write" on the picture. Unfortunately, Corel only has a Plug-In for
Win 95/NT, so this won't work with Win 3.1 or Mac.
_________________________________________________________________
Sometimes, it doesn't go this way: sometimes serendipity (Serendib =
former name for Ceylon) happens. The Persian fairy-tale The Three
Princes of Serendip illustrates the principle known as serendipity.
In this story, three princes make discoveries by insight into
accidents pertaining to things they were not seeking. Serendipity is
not discovery just by accident alone, but includes the idea that the
investigator has intuition, or knowledge, which enables him/her to
recognize and take advantage of unexpected events unrelated to his/her
original quest. The discovery of aspartame is a good example of
serendipity, but also an example of very bad lab technique. A chemist
at Searle Chemical Company had his coffee cup sitting on the benchtop
in the chemistry lab next to his experiment. Somehow in the process of
doing his experiment and drinking coffee all at the same time (not a
good idea if you value your life), he stuck his fingers in his
experiment, then into his mouth. The serendipity comes in when he
realized that this sweet-tasting accident could make his company and
him rich.
_________________________________________________________________
To give you an idea of how the scientific method works, your study
group is asked to go through the steps we just discussed as though you
were real biologists getting ready to do real research. You will be
doing all of the background work and designing the experiment, but not
actually doing it since this is not a lab course. However, you are
asked to do a write-up of the experiment as though you had done it.
For more information on this, refer to the Assignment on Scientific
Method that was handed out along with your syllabus.
Now that we have some of the background out of the way, we will start
with atoms then molecules like water, then work our way up to living
organisms.
Back to the Biology 104 syllabus
_________________________________________________________________
Copyright © 1996 by J. Stein Carter. All rights reserved.
This page was created using Corel ®</sup> Presentations™ 8.
Copyright © 1997 Corel Corporation Limited.
The MIDI file was obtained from one of the many MIDI Collection Web
sites, and contained no copyright or author/sequencer information.