9/4/2013
9.4.13
Bell work:
• What is a control group?
▫ The part of the experiment
that is used for comparison.
It is the part NOT being
tested.
Objectives:
I will…
• Review the parts of the
scientific method.
Turtles Ahoy! (A real implementation
of the scientific method)
Did you ever wonder how baby sea turtles can run down into the ocean after hatching, paddle
thousands of miles across the North Atlantic, and find their way back years later to the same
beach they were born?
Curious about these creatures, a biologist at University of North Carolina at Chapel Hill has
discovered at least part of the answer. Baby loggerhead turtles, no bigger than a child’s hand,
use the Earth’s magnetic fields and waves to orient themselves and direct their marathon
swims.
In a recent issue of Scientific American magazine, biologist Kenneth Lohmann describes
experiments showing their biological compass. Working with Florida Atlantic University
science researchers, Lohmann tied loggerhead turtle hatchlings (newborns) to a device and
placed them in a large glass tank filled with water.
Within minutes of placing the hatchlings in total darkness, researchers observed that the
turtles all swam in the same direction. In fact, most of them swam towards points located
between magnetic north and east, directions that would lead them away from Florida’s east
coast and toward the Gulf Stream currents. The biologists also found that when they reversed
the magnetic field, the turtles swam in the opposite direction- toward the southwest.
Homework: Turtles Ahoy!
Review time!
• 1. Circle and label the question that is going to be
investigated.
• 2. What is the hypothesis?
• 3. What is the independent variable?
• 4. What is the dependent variable?
• 5. What are the constants?
• 6. Describe the data and analysis.
• 7. What is the conclusion?
Scientific Method
Tables, charts, and graphs are
often a part of which step of the
scientific method?
Review Game
Analyze
Results
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9/4/2013
The ____________ variable is
the variable which is being
affected by the independent
variable.
Dependent
The part of the experiment that
is used for comparison. It is the
part NOT being tested.
Control
Group
What step of the scientific method
is this?
“If I use place the basil in direct
sunlight, then it will grow higher,
because basil needs a lot of sun.”
A
hypothesis
Is the statement below an
observation or inference?
“The plant has 5 new leaves and
is 15 cm tall”
Observation
List the 8 steps of the scientific
method in order.
1.Problem
2.Observation
3.Hypothesis
4.Experiment
5.Collect Data
6.Analyze Results
7.Conclusion
8.Report findings
The one thing being tested and
is therefore changed between
parts of the experiment is called
the _______ ________.
Independent
Variable
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_________ data is numerical
measurements.
Quantitative
For an experiment to be
controlled, how many constants
can you have?
Any
number!
Sponge Bob notices that his pal Gary is suffering from
slimotosis, which occurs when the shell develops a nasty slime
and gives off a horrible odor. His friend Patrick tells him that
rubbing seaweed on the shell is the perfect cure, while Sandy
says that drinking Dr. Kelp will be a better cure. Sponge Bob
decides to test this cure by rubbing Gary with seaweed for 1
week and having him drink Dr. Kelp. After a week of
treatment, the slime is gone and Gary’s shell smells better.
What is the experimental question?
What is the best way to
get rid of slimotosis?
_________ data is a description
of the observations made during
an experiment.
Qualitative
A short statement of whether or
not your results support your
hypothesis is called a(n)
______________ .
Conclusion
Sponge Bob notices that his pal Gary is suffering from
slimotosis, which occurs when the shell develops a nasty slime
and gives off a horrible odor. His friend Patrick tells him that
rubbing seaweed on the shell is the perfect cure, while Sandy
says that drinking Dr. Kelp will be a better cure. Sponge Bob
decides to test this cure by rubbing Gary with seaweed for 1
week and having him drink Dr. Kelp. After a week of
treatment, the slime is gone and Gary’s shell smells better.
Name the independent variable(s).
(type of treatment):
Seaweed treatment and
Dr. Kelp
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9/4/2013
Sponge Bob notices that his pal Gary is suffering from
slimotosis, which occurs when the shell develops a nasty slime
and gives off a horrible odor. His friend Patrick tells him that
rubbing seaweed on the shell is the perfect cure, while Sandy
says that drinking Dr. Kelp will be a better cure. Sponge Bob
decides to test this cure by rubbing Gary with seaweed for 1
week and having him drink Dr. Kelp. After a week of
treatment, the slime is gone and Gary’s shell smells better.
Is this a controlled experiment? Why or why not?
No, too many
independent variables.
Sponge Bob notices that his pal Gary is suffering from
slimotosis, which occurs when the shell develops a nasty slime
and gives off a horrible odor. His friend Patrick tells him that
rubbing seaweed on the shell is the perfect cure, while Sandy
says that drinking Dr. Kelp will be a better cure. Sponge Bob
decides to test this cure by rubbing Gary with seaweed for 1
week and having him drink Dr. Kelp. After a week of
treatment, the slime is gone and Gary’s shell smells better.
How could Sponge Bob fix this experiment?
Sponge Bob notices that his pal Gary is suffering from
slimotosis, which occurs when the shell develops a nasty slime
and gives off a horrible odor. His friend Patrick tells him that
rubbing seaweed on the shell is the perfect cure, while Sandy
says that drinking Dr. Kelp will be a better cure. Sponge Bob
decides to test this cure by rubbing Gary with seaweed for 1
week and having him drink Dr. Kelp. After a week of
treatment, the slime is gone and Gary’s shell smells better.
What should Sponge Bob’s conclusion be?
It is unclear which method
caused the slimotosis to go
away. He should conclude that
he must redo the experiment.
What would be the benefit of having a control
group when redoing the experiment.
He should test the two solutions
on two groups of snails with
slimotosis. He should also
include a control group.
You can see if the slimotosis
goes away on its own.
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Use the if…then…because format to say Mr. Krabs hypothesis.
If the customers eat the new sauce,
then their gas will go away, because
it contains a gas reduction
ingredient.
Which group is the control group?
The group with the mayonnaise
and food coloring.
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9/4/2013
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Name the independent variable(s).
The type of sauce on the crabby
patty.
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Name three(3) constants in this experiment.
1. 50 people per group
2. People eat crabby patties
3. All were told the sauce
reduces gas
Mr. Krabs has created a new sauce that he thinks will reduce the production
of body gas associated with eating crabby patties from the Krusty Krab. He
recruits 100 customers with a history of gas problems. He has 50 of them
(Group A) eat crabby patties with the new sauce. The other 50 (Group B)
eat crabby patties with sauce that looks just like new sauce but is really
just mixture of mayonnaise and food coloring. Both groups were told that
they were getting the sauce that would reduce gas production. After eating
the crabby patties, 30 customers in group A reported having fewer gas
problems and 8 customers in group B reported having fewer gas problems.
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Name the dependent variable(s).
Gas production
Mr. Krabbs has created a new sauce that he thinks will reduce the
production of body gas associated with eating crabby patties from the
Krusty Krab. He recruits 100 customers with a history of gas problems. He
has 50 of them (Group A) eat crabby patties with the new sauce. The other
50 (Group B) eat crabby patties with sauce that looks just like new sauce
but is really just mixture of mayonnaise and food coloring. Both groups
were told that they were getting the sauce that would reduce gas
production. After eating the crabby patties, 30 customers in group A
reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
Is this a controlled or uncontrolled experiment? Why?
Controlled. There is only 1
independent variable.
Closing Question
• Write a possible hypothesis for the following
experimental question:
What should Mr. Krabs’ conclusion be?
His hypothesis was correct, the
new sauce helps prevent
customers from getting gas.
• Does temperature affect the rate of respiration in
gold fish?
• Remember to use “If…then…because…”
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