- [Bill] Today we're going to look at how scientists go about investigating
phenomenon and trying to gather some information. So, we're going to look at
steps of what we call the scientific method. Now, these steps are more of a
process than absolutely set in stone. Different scientists might list them in
a slightly different way but again it's emphasizing the process of trying to
do an investigation scientifically that we want to emphasize in this lesson. So, we're
going to start off with observations, and observations sometimes are left out when
people are talking about this process but I believe it's very, very important that
we include those. What observations do is, they raise the curiosity of a scientist
or an investigator. People do science all the time, they just don't think about it
in that context, so it's not just limited to scientists. Let me start off with the
specific example with observations. And we're going to go back several centuries
and we're going to look at the work of a microbiologist whose name was Alexander
Flemming. And Alexander Flemming was trying to grow bacteria on a small, little
dish called a petri dish and what he was finding was that his petri dishes, that
he was trying to grow bacteria, kept being infected with mold, which was common back
in those days. We didn't know a whole lot about good techniques, or certainly not
what we know now and so mold contamination was a fairly common event.
But what Flemming actually noticed,
and this is my point about the observation, is that he noticed
that while bacteria was growing all over the dish, it was not growing around the
mold and he was the first one to really observe this or wonder what was going on
here. So, he made the observation that the bacteria does not seem to be growing
around the mold. Well, that led him to the next step as we're going through our
scientific method here, of the question. And his question then was,
"Well, why isn't bacteria growing around the mold?" Well, he came up then with an
educated guess. An educated guess is a hypothesis. Now, these two go connected,
so a hypothesis is an educated guess which answers the question. It's not just
simply a random educated guess. It all ties in with our observations, question,
hypothesis. But because he made this observation, he asked a question, he
came up with a hypothesis that the mold has some sort of factor in it that kills
bacteria or prevents bacteria growth and based on this observation, which other
people hadn't made before, this actually led to the discovery of the
antibiotic Penicillin. So again, observation, very important point.
Alexander Flemming's observation has now saved countless lives.
Well, once we get a hypothesis or an educated guess, then we, the scientist or
just the individual will do an experiment. And we're going to actually look at the
experiment in a little bit later in this particular lesson. Finally, the last step
of the scientific method is a conclusion. And the conclusion is just a simple
statement, it doesn't have to be complex and a conclusion summarizes the results of
the experiment. We usually just say something like, the results of this
experiment either support our hypothesis; sometimes it actually does the opposite.
We may say that the results refute the hypothesis. And sometimes the results
don't tell us much. It's kind of frustrating when that happens but
sometimes that is what happens, or we say the results are inconclusive. So, our steps
of the scientific method are observation, question, hypothesis, experiment and
conclusion. And shortly, we'll be going through proper experimental design.
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