Scientific Method

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Scientific Method

• Yeast Lab!

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What makes something living?

• Consider the following questions
• How big/complex must something be?
• What must it be able to do?
• Where must it come from?
• What are the essential components?
• How is it different from something nonliving?
• Is seeing believing??????
• http//www.youtube.com/watch?vjuxLuo-sH6M

Is Yeast living?
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So, what makes something living?

• 1. Living things are based on a universal genetic
  code.
• All organisms store the complex information they
  need to live, grow, and reproduce in a genetic
  code written in a molecule called DNA!
• The information is copied and passed on from
  parent to offspring.
• With a few minor variations, lifes genetic code
  is almost identical in every organism on Earth.

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• 2. Living things grow and develop.
• Every organism has a particular pattern of growth
  and development.
• During development, a single fertilized egg
  divides and divides again.
• As these cells divide, they differentiate, which
  means they begin to look different from one
  another and perform different functions.

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• 3. Living things respond to their environment.
• Organisms detect and respond to stimuli from
  their environment.
• A stimulus is a signal to which an organism
  responds.

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• 4. Living things reproduce.
• All organisms reproduce, which means that they
  produce new similar organisms. Most plants and
  animals engage in sexual reproduction.
• In sexual reproduction, cells from two parents
  unite to form the first cell of a new organism.
• Other organisms reproduce through asexual
  reproduction, in which a single organism produces
  offspring identical to itself.

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• 5. Living things maintain a stable internal
  environment.
• Most organisms need to keep conditions inside
  their bodies as constant as possible, even when
  external conditions change dramatically.
• All living organisms expend energy to keep
  conditions inside their cells within certain
  limits. This process is called homeostasis.

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• 6. Living things obtain and use materials and
  energy.
• All organisms must take in materials and energy
  to grow, develop, and reproduce.
• The combination of chemical reactions through
  which an organism builds up or breaks down
  materials is called metabolism.

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• 7. Taken as a group, living things evolve.
• Over generations, groups of organisms evolve, or
  change over time.
• Evolutionary change links all forms of life to a
  common origin more than 3.5 billion years ago.
• Evidence of this shared history is found in all
  aspects of living and fossil organisms, from
  physical features to structures of proteins to
  sequences of information in DNA.

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• 8. Living things are made up of cells.
• Organisms are composed of one or more cells- the
  smallest units considered fully alive.
• Cells can grow, respond to their surroundings,
  and reproduce.
• Despite their small size, cells are complex and
  highly organized.

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Characteristics of life summary

• http//www.youtube.com/watch?vuM_CgOgJGG0
• 1. Living things are based on a universal genetic
  code.
• 2. Living things grow and develop.
• 3. Living things respond to their environment.
• 4. Living things reproduce.
• 5. Living things maintain a stable internal
  environment (homeostasis).
• 6. Living things obtain and use materials and
  energy (metabolism).
• 7. Taken as a group, living things evolve.
• 8. Living things are made up of cells.

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Scientific Method Summary

• Make Observations and Ask Questions
• Form a Hypothesis
• Design an Investigation
• Test the Predictions
• Analyze the Results
• Conclusion

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Make Observations and Ask Questions

• Describe what you can see, taste, smell, feel,
  etc!
• What is yeast? What would it need to be
  considered living?
• What will we be looking at in this experiment

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Form a Hypothesis

• Hypothesis
• is a possible explanation for an observation or a
  scientific problem that is given to you.
• Must include only one independent variable
• Example If you increase the light intensity,
  then the plant growth rate will increase.

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Design an Investigation

• Identify the variables
• Independent variable
• Set by the person carrying out the investigation
  (ex. time , temperature, light intensity, pH)
• Dependent variable
• Measured during the investigation (ex. plant
  growth, heart rate etc)
• Controlled variable
• Factors that are kept the same or controlled.
  (ex. Amount of water, fertilizer, temperature)

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Design an Investigation

• An experiment typically contains a
• Control group
• Exposed to the same conditions as the
  experimental group except for one independent
  variable.
• Serves as a standard for comparison to the
• Experimental group
• The group that the independent variable is
  applied to.

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Test the Predictions

• Use step by step procedure to perform your
  experiment

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Analyze the Results

• Discuss trends in the data you collected in your
  experiment
• You may have to perform calculations depending on
  the data you collect

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Conclusion

• Does your data all0w you to support or reject
  your hypothesis?
• What did you learn from this experiment, and how
  does this connect to the knowledge you had going
  into the experiment?
• How would you do the experiment if you were to
  perform it again?

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Scientific Method Summary

• Make Observations and Ask Questions
• Form a Hypothesis
• Make Predictions
• Design an Investigation
• Test the Predictions
• Analyze the Results
• Conclusion