4. OBSERVATION
• Leads to a question that may be descriptive or causal
• Casual questions are the heart of scientific inquiry
• Casual questions can only be posed after descriptive questions have been answered.
• Another objective of Concepts in Plant Biology is to give you experience with science as an
activity and scientific inquiry. Scientific inquiry involves
observing, questioning, experimenting, analyzing and verifying or discarding of information. For
the beginner, it is easiest to view scientific inquiry as a series of steps referred to as the scientific
method.
• The scientific method begins with an observation of nature or the physical world.
• The observation leads to a question that may be either descriptive or causal.
• For example, you may observe a giant redwood tree and wonder about the pathway water
takes to get to the top of the tree.
• This is a descriptive question. Alternatively, you may ask what causes the water to reach the top
of the tree. This is a causal question. Causal questions are the heart of scientific inquiry
but, often, can only be posed after descriptive questions have been answered.
5. QUESTIONING
• Questioning can be applied to everyday situations.
• Common occurrences provoke casual questions.
• The scientific method can also be applied to everyday situations.
• Such as:
• You go out to start your car and the engine fails to turn over.
• The light in the living room fails to come on when you flip the switch.
• You always sneeze violently when you go to a particular friend's house.
• (Click mouse) Each of these common occurrences provoke causal
questions: Why won't the light turn on or the engine start? Why do you
start sneezing in this particular place?
• Take a look at the following video clip about the scientific method.
• Let's follow rest of steps of the scientific method to answer the latter
question.
6. HYPOTHESIS
• A reasonable possible answer for the observation
• Unproven explanations
• Must be consistent with previous observations.
• nce you have a causal question, the next step is to generate a hypothesis – a reasonable
possible answer for the observation. (click mouse)
• Hypotheses are plausible but unproven explanations based on your previous experiences or
experiences of others, by analogy, and by creativity. In our example, you know people with
allergies start sneezing when they come in contact with something that causes the allergy.(Click
mouse)
You hypothesize that you must be allergic to something in or around that house. But what? The
family has a cat and you know some people are allergic to cats. Perhaps it's the cat.
However, they also have rabbit, so perhaps it's the rabbit. The family cultivates orchids. Maybe
it's the orchids. These are plausible explanations- or alternative hypotheses for your sneezing
episodes.
An important factor to consider when formulating hypotheses is that the hypothesis must be
consistent with previous observations. If you have been in the presence of other cats and never
had a sneezing attack, then the cat allergy hypothesis is not consistent with previous
observations. (click mouse)
7. EXPERIMENTING
• Test hypotheses by experimentation
• Experiment is a set of manipulation or observations
of that nature that test a particular hypothesis.
After posing alternative hypotheses, the next step is to test the
hypotheses by experimentation. An experiment is a set of
manipulations or observations of nature that test a particular
hypothesis. For example, to test the hypothesis that you are
allergic to rabbits you might visit other friends who have rabbits
that roam the house freely. You would expect to start sneezing
in these houses also, if you are allergic to rabbits. To test the
hypothesis about the orchid allergy, you may visit the orchid
display at a local botanical garden or nursery and monitor your
response. If you were allergic to orchids, then you would expect
to start sneezing under these situations.
8. ANALYZING AND VERIFYING
INFORMATION
• Compare observed results with expected results
• From comparison make interpretations and conclusions
• Note that in each of these "experiments", you have expected results, based upon
the assumption that the hypothesis is correct.
• Once the experiment is performed, the investigator can compare the observed
results with the expected results. (click mouse)
• From this comparison, you can make interpretations and conclusions. For
example, if you go to another house with a rabbit and have mild sneezing
attack, you would conclude that you are allergic to rabbits (hypothesis was
supported) but that the severity of your allergy depends upon some additional
factor (interpretation). This interpretation raises a new question, poses new
hypotheses, further testing, etc. (click mouse)
• Indeed that is the nature of science as an activity. If the hypothesis is not
supported, that is, you do not sneeze in the presence of other rabbits, then you
need to consider alternative hypotheses and follow through with the scientific
method. Note that in both situations (hypothesis supported or not supported), you
have learned something by applying the scientific method.
9. EXPERIMENTAL DESIGN
A well designed experiment includes the following:
• An experimental group (groups) and a control(s)
• Each experimental and control group consist of many samples or individuals
• The experiment is replicated (repeated) several times
Science only deals with observations and phenomenon that are testable by experimentation
and cannot address questions of the supernatural or spiritual because they are not testable.
Thus, experimentation is an essential part of science. As stated previously an experiment is a set of
manipulations or observations of nature that is designed to test a hypothesis. Although we may
think of experiments as being conducted in the laboratory, they may also be done in the out-of-
doors. Depending upon the nature of the question, nature may be manipulated or simply
observed. For example, if you want to know the effect of fire on germination of pine seeds, you
might have a control burn (a manipulation). If you want to know what animal pollinates the
saguaro cactus flower, you would simply watch to see what the animals visit the flowers
(observations).
A well-designed experiment includes the following:
1) An experimental group (groups) and a control(s)
2) Each experimental and control group consist of many samples or individuals
3) The experiment is replicated several times
Editor's Notes
Another objective of Concepts in Plant Biology is to give you experience with science as an activity and scientific inquiry. Scientific inquiry involves observing(click mouse), questioning(click mouse), experimenting(click mouse), analyzing(click mouse), and (click mouse), verifying or discarding of information. For the beginner, it is easiest to view scientific inquiry as a series of steps referred to as the scientific method.
The scientific method can also be applied to everyday situations.method to answer the latter question.
