Inv and Exp

1
Investigation and Experimentation

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  should only be used for educational purposes
  (Fair Use Policy)

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Find the Safety Mistakes
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Observations

• 5 senses
• Qualitative
• Color
• Smell
• Etc.
• Quantitative
• Can measure
• Length, width, mass, etc.

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Is It Alive?

• Look at these photographs of living things. Then,
  make a list of some of the characteristics of
  living things they suggest.

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What do you see?

• Do any questions come to mind?
• Why are yellow-flowered plants grow on one side
  of the field but not the other?
• What could have caused this pattern?

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Notes

• Characteristics of Life
• 1. Have cells
• 2. Can reproduce
• 3. Grow and develop
• 4. Need energy
• 5. Respond to environment
• Living things have all 5 characteristics
• Organisms are living things

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Under the Microscope
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Is It Alive?

• Which characteristic of living things does each
  one illustrate? Decide whether each picture
  represents something that is alive or not alive.

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Notes

• Steps to Scientific Method
• record observations
• form a hypothesis
• test
• analyze data

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Notes

• Parts of an experiment

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Notes

• Problem a question investigated
• Example Does eating chocolate cause pimples?

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Redis Experiment

• What is the problem?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
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Notes

• Hypothesis is an educated guess or prediction
• Must be testable
• Results do not have to fit the hypothesis
• Example I predict that chocolate causes pimples.

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Redis Experiment

• What can be the hypothesis?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
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Notes

• Independent variable a condition tested
• Example the chocolate

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Redis Experiment

• What is the independent variable?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Independent Variable Uncovering the jar
Maggots appear
No maggots appear
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Notes

• Constants are conditions that the experimenter
  keeps the same between the groups
• Example same amount of chocolate, same type of
  chocolate, same number of subjects tested, same
  temp, location, etc.

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Redis Experiment

• What are the constants?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Constants jars, type of meat, location,
temperature, time
Several days pass
Maggots appear
No maggots appear
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Notes

• Dependent variable is the observed or measured
  effect of the independent variable
• Example observing how many pimples appear

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Redis Experiment

• What is the dependent variable?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Dependent Variable Observing whether maggots
appear
Maggots appear
No maggots appear
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Notes

• Experimental Group has the independent variable
• Example the group given chocolate
• Control Group does not have independent
  variable
• Example the group not given chocolate

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Redis Experiment

• Which is the experimental group? Control group?
  (Right or left set-up)

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Experimental Group
Control Group
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
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Notes

• Procedures steps in an experiment
• Allows retesting of the same experiment
• Prevents experimental error

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Redis Experiment

• What can be the procedures?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
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Notes

• Experimental Error
• When factors other than the independent variable
  can affect the results
• Can be reduced by
• Ensuring all other factors are constant
• Repeating your experiment
• Having large groups to sample
• Example
• When testing to see whether eating chocolate
  causes pimples, other factors like the type and
  amount of chocolate, other kinds of food eaten,
  type of subjects may affect your results
• To reduce the error, ensure all other factors are
  constant (same and amount of chocolate, same
  kinds of food eaten, similar types of subjects )

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Redis Experiment

• What could be some experimental errors here?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Experimental Group
Control Group
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
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Notes

• Conclusion A statement that summarizes the
  findings of your experiment
• Example Chocolate does not cause pimples.

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Redis Experiment

• What can be the conclusion?

OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Several days pass
Maggots appear
No maggots appear
CONCLUSION Flies do produce maggots.
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Redis Experiment
OBSERVATIONS Flies land on meat that is left
uncovered. Later, maggots appear on the meat.
PROBLEM Do flies cause maggots to appear?
HYPOTHESIS I predict that flies produce maggots.
PROCEDURE
Experimental Group
Control Group
Uncovered jars
Covered jars
Constants jars, type of meat, location,
temperature, time
Several days pass
Independent Variables Uncovering the jars
Dependent Variable Observing whether maggots
appear
Maggots appear
No maggots appear
CONCLUSION Flies do produce maggots.
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Practice

• Smithers thinks that a special juice will
  increase the productivity of workers. He creates
  two groups of 50 workers each and assigns each
  group the same task (in this case, they're
  supposed to staple a set of papers). Group A is
  given the special juice to drink while they work.
  Group B is not given the special juice. After an
  hour, Smithers counts how many stacks of papers
  each group has made. Group A made 1,587 stacks,
  Group B made 2,113 stacks.

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Problem Hypothesis
Groups A B
Independent variable Constants Dependent
variable Results
Set-up During End
Conclusion
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Spallanzanis Experiment

• Find the following
• Independent variable
• Constants
• Dependent variable

Gravy is boiled.
Flask is open.
Gravy is teeming with microorganisms
Flask is sealed.
Gravy is free of microorganisms.
Gravy is boiled.
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Spallanzanis Experiment

• Find the following
• Experimental Group
• Control Group
• Conclusion

Gravy is boiled.
Flask is open.
Gravy is teeming with microorganisms
Flask is sealed.
Gravy is free of microorganisms.
Gravy is boiled.
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Notes

• Theory
• a statement of related hypotheses that have been
  tested and confirmed.
• unites and explains a broad range of observations
  and evidence.
• makes useful predictions.
• can change based on new evidence.

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Notes
Theory
Hypothesis
Hypothesis
Fact (Observation)
Fact (Observation)
Fact (Observation)
Fact (Observation)
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Theories

• All cells come from pre-existing cells (Cell
  Theory)
• All organisms evolved from the first life form on
  Earth (Theory of Evolution)

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Testing a Theory is Rough Business

• For a long time, people accepted the Geocentric
  Theory that the sun, stars, and planets
  revolved around the Earth.
• Careful observations made by later scientists
  didnt fit this model, and it was eventually
  scrapped in favor of the Heliocentric Theory.

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Practice

• Suppose you did an experiment where you were
  testing whether a chemical caused cancer on the
  skin. How would you design this experiment?

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Problem Hypothesis
Groups A B
Independent variable Constants Dependent
variable Results
Set-up During End
Conclusion
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Multiple Choice Tips

• Answering about 1/2 the questions correctly will
  get an average score
• Questions go from easy to hard, with questions on
  graphics, charts data tables at the end
• Skip questions you dont understand and come
  back to if there is time

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Multiple Choice Tips

• Read test directions carefully before you begin
  to mark any answers.
• If directions are not clear,
  ask for clarification
  before you begin
• Keep track of the time
• Budget your time accordingly.

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Multiple Choice Tips

• All questions are worth 1 point, regardless of
  difficulty
• If you can eliminate one or two wrong answers to
  a questions, it is best to guess at the answer

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Pace Yourself

• Make sure that you're not working too slowly.
• You should have answered at least half the
  questions in a section when half the time for
  that section has passed.

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Reading Tips

• Read the entire question including all the answer
  choices before answering a question.
• Don't think that because the first or second
  answer choice looks good to you, it isnt
  necessary to read the remaining options.

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Key Words

• may
• must
• necessary
• never
• none
• not
• often

• only
• perhaps
• rarely
• seldom
• sometimes
• usually
• all
• always
• but
• except
• every
• generally
• however

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Reading Tips

• When a question or answer option contains words
  such as "always," "every," "only," "never," and
  "none," there can be no exceptions to the answer
  you choose.
• Use of words such as "often," "rarely,"
  "sometimes," and "generally" indicates that there
  may be some exceptions to the answer.

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Donts

• Don't select an alternative just because you
  remember learning the information in the course
• Don't pick an answer just because it seems to
  make sense.
• You are answering from your content knowledge,
  not just from your general logic.
• Don't dismiss an alternative because it seems too
  obvious and simple an answer.

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Donts

• Don't be wowed by fancy terms don't say to
  yourself, "That sounds impressive, so it must be
  the right answer!"
• Don't pick "c" every time you are unsure of the
  answer. You could end up picking "c" far too many
  times.
• Don't pick your answer based on a pattern of
  responses, i.e., don't say to yourself, "This
  can't be another "b" answer as we have just had
  three in a row."

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Caution

• MAKE SURE TO ERASE ALL STRAY MARKS ON THE SIDE OF
  A SCAN-TRON BEFORE YOU TURN IN THE TEST!!!!
• (the machine will count a stray mark answer and
  mark the question incorrect.)