Entry task-September 15

1
Entry task-September 15

• Look at your returned Heart rate, correct
  anything I wrote comments on. Remind yourself
  what the purpose of the experiment was. Now
  write the answers to the conclusion questions in
  complete sentences.

2
How to write a Conclusion

• You asked a question, you did an experiment, and
  you did the experiment a second time. You
  recorded your results. Now it is time to write
  your conclusion. The conclusion, plain and
  simple, is the answer to your question. It should
  be clear, concise and stick to the point. Resist
  the temptation to jump to conclusions.
•  If you were to do your experiment again, would
  you get the same results?
• Can there be differences? Why?
• Ask yourself what happened when you tested your
  hypothesis.
• What have you learned from this experiment? What
  does this experiment tell us
• Now for homework-- using the answers to the
  questions on the heart rate lab, write a final
  report summarizing your question, research
  methods and conclusion. Must be printed neatly
  or typed (5 points extra credit)

3
Agenda

• Entry task
• Conclusion writing and homework instructions
• Daphnia Lab Instructions
• Daphnia Lab
• Homework Conclusion for heart rate lab on
  separate sheet of paper in paragraph style

4
Learning targets

1. I can write a scientifically based conclusion
2. I can perform an experiment on a living organism
   to test the effects of different chemicals.

5
Review of Microscope

• Use your assigned microscope and return it to its
  proper place as instructed
• Always start on low power
• Make sure your lenses are clean
• We will be using depression lenses, make sure
  your Daphnia is in the well and do not overflow.

6
Bioassays

• Dose/Response Bioassays are used to
• Estimate toxicity to humans.
• Estimate maximum concentrations of specific
  chemicals allowed to discharge into bodies of
  water.
• Investigate hazardous waste sites.

7
Bioassay Species

• 3 organisms are often used
• Daphnia
• Duckweed
• Lettuce Seeds
• Expose organisms to chemicals and measure how
  they respond.

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8
Remember you are working with a living creature

• http//www.microscopyu.com/moviegallery/pondscum/d
  aphnia/
• At the end of each experiment return your daphnia
  to the Rehabilitation and Recovery area on the
  demonstration desk. Use a new daphnia for each
  chemical

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Daphnia
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Part 1

• Take a look at your daphnia on low power-use the
  sketch I put on the overhead to help sketch and
  label your daphnia
• Look at your daphnia on medium power and sketch
  and label what you see
• Do not use high power with daphia or well plates

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Part 2

• Make sure to get a new daphnia for each chemical
  you try
• You will need a timer to do the heart rate
• Make sure to record beats/min
• Return daphnia to the rehab bowl
• Clean up your lab station and return your
  microscope to the cabinet as directed

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Data

• Make sure to put your averages into the data
  table at my desk
• Make sure to write down the class average
• Graph your data using a bar chart, showing your
  averages and the class averages

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Conclusion

• If time permits fill in the conclusion parts of
  the lab. Next class we will use this information
  and some background information about the drugs
  to build a more complete conclusion
• Turn in your lab report whether you complete the
  report or not.