Transcript Scientific Method

Scientific Method
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What can an elephant teach us
about the scientific method??
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A poem written by John Godfrey Saxe (1816-1887)
It was six men of Indostan
To learning much inclined
Who went to see the Elephant
(Though all of them were blind),
That each by observation
Might satisfy his mind
The First approached the Elephant,
And happening to fall
Against his broad and sturdy side,
At once began to bawl:
"God bless me! but the Elephant
Is very like a wall!"
The Second, feeling of the tusk,
Cried, "Ho! what have we here
So very round and smooth and sharp?
To me 'tis mighty clear
This wonder of an Elephant
Is very like a spear!“
• The Third approached the animal,
And happening to take
The squirming trunk within his hands,
Thus boldly up and spake:
"I see," quoth he, "the Elephant
Is very like a snake."
The Fourth reached out an eager hand,
And felt about the knee.
"What most this wondrous beast is like
Is mighty plain," quoth he;
"Tis Clear enough the Elephant
Is very like a tree."
The Fifth, who chanced to touch the ear,
Said: "E'en the blindest man
Can tell what this resembles most;
Deny the fact who can,
This marvel of an Elephant
Is very like a fan!"
• The Sixth no sooner had begun
About the beast to grope,
Then seizing on the swinging tail
That fell within his scope,
"I see," quoth he, "the Elephant
Is very like a rope."
And so these men of Indostan
Disputed loud and long.
Each in his own opinion
Exceeding stiff and strong,
Though each was partly in the right,
And all were in the wrong.
• 1. How does this poem illustrate the importance
of observation in the scientific method?
• 2. What is the moral of the tale?
• 3. Many scientific errors can occur because
the researcher does not use good skills of
observation. Imagine a scenario where not
being observant can result in an experiment
going wrong. Describe this scenario in the
form of a story or a poem.
Scientific Method
involves a series of
steps that are
used to
investigate a
natural
occurrence.
Problem
Formulate a Hypothesis
Experiment
Collect and Analyze
Results
Conclusion
Communicate the
Results
• Steps of the
Scientific Method
1. Problem: Develop a
question or problem
that can be solved
through
experimentation.
Examples:
Testable problem: How can
we make a sunflower
grow taller?
Not Testable: What is the
meaning of life?
2. Formulate a
Hypothesis: Predict a
possible answer to
the problem or
question.
Example: If soil temperatures
rise, then plant growth will
increase.
3. Experiment: Test your
hypothesis.
• Manipulated variable:
the ONE thing you
change. Example:
cancer treatment pill
given
• Responding variable:
what changes because
of the manipulated
variable. Example: the
cancer growth stops
• Two groups are used…
Cancer Growth
– Control group:
nothing is changed
with this group (they
do not get the cancer
treatment pill but a
placebo instead)
– Experimental group:
this group receives
the manipulated
variable (they get the
cancer treatment pill)
Experimental
Group
Control Group
4. Collect and Analyze
Results: Modify the
procedure if needed.
Confirm the results by
retesting.
Include tables, graphs,
and photographs.
5. Conclusion:
Include a
statement that
accepts or rejects
the hypothesis.
Make
recommendations
for further study
and possible
improvements to
the procedure.
6. Communicate
the Results:
share your
results with
others.
Scientific Method In Action
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The Strange Case of BeriBeri
In 1887 a strange nerve disease attacked the people in the Dutch
East Indies. The disease was beriberi. Symptoms of the disease
included weakness and loss of appetite, victims often died of heart
failure. Scientists thought the disease might be caused by bacteria.
They injected chickens with bacteria from the blood of patients
with beriberi. The injected chickens became sick. However, so did a
group of chickens that were not injected with bacteria.
One of the scientists, Dr. Eijkman, noticed something. Before the
experiment, all the chickens had eaten whole-grain rice, but during
the experiment, the chickens were fed polished rice. Dr. Eijkman
researched this interesting case. he found that polished rice lacked
thiamine, a vitamin necessary for good health.
1. State the Problem
2. What was the hypothesis?
3. How was the hypothesis tested?
4. Should the hypothesis be supported or rejected based on the
experiment?
5. What should be the new hypothesis?
• How Penicillin Was Discovered
• In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria
growing in culture dishes. He noticed that a mold called Penicillium was also
growing in some of the dishes. A clear area existed around the mold because
all the bacteria that had grown in this area had died. In the culture dishes
without the mold, no clear areas were present.
• Fleming hypothesized that the mold must be producing a chemical that
killed the bacteria. He decided to isolate this substance and test it to see if it
would kill bacteria. Fleming transferred the mold to a nutrient broth
solution. This solution contained all the materials the mold needed to grow.
After the mold grew, he removed it from the nutruient broth. Fleming then
added the nutrient broth in which the mold had grown to a culture of
bacteria. He observed that the bacteria died.
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6. Identify the problem.
7. What was Fleming's hypothesis?
8. How was the hypothesis tested?
9. Should the hypothesis be supported or rejected based on the
experiment?
• 10. This experiment led to the development of what major medical
advancement?