2. Objective: To follow the steps to conduct a controlled experiment  Hypothesis  Independent variable  Dependent variable  Control Group/Experimental Groups  Constants  Graph data  Conclusions based on data from graph  Support or refute hypothesis

3. Comparing Hypotheses, Theories, and Laws

4. People often misinterpret the language used by scientists. Here is what each of these terms means to a scientist:

5. Hypothesis: This is an educated guess based upon previous knowledge. Must be a statement, never a question. I THINK THAT……… (testable) If I pass the mouse over the action button, then I will return to the appropriate slide.

6. Theory Theory - is an idea, or a set of guiding principles to explain a phenomenon. Ex: The scientific principles of evolution that are used to explain human life are an example of the theory of evolution. One scientist cannot create a theory, it takes many ideas combined.

7. Theory Continued A theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole.

8. Scientific Law This is a statement of fact and universal, and usually SIMPLE Ex: The Law of _______________ A law governs a single action, whereas a theory explains a whole series of related phenomena.

9. Define the Problem- What are we trying to figure out in the form of a question State the Hypothesis- an educated guess (I think that) Controlled Experiment- experiment with least 2 groups with only 1 difference between them Collect Data – charts, tables, graphs Qualitative- description Quantitative- measurement/numbers Draw Conclusions Must support or refute hypothesis Include possible errors

10. Scientific Method in action  Spontaneous Generation?? Spontaneous Generation?? Spontaneous Generation??

11. MUST KNOW WORDS:  Control Group: group used as a comparison for experimental group (closest to NORMAL)  Experimental Group: group that has what you are testing (has ONE diff compared to control)  Factors that are kept the same- everything EXCEPT for the ONE difference  Independent Variable:  Independent Variable: (manipulated variable)  The 1 difference before experiment even starts  Dependent Variable:  Dependent Variable: (responding variable)  Data (you record)  The thing you measure/record

12. Other MUST knows:  Ways to make an experiment more RELIABLE or VALID  Larger sample size  Repeat  Ways to Organize your results  Tables  Graphs  Charts

13. Example 1: A new plant fertilizer claims it will double the size of your crops in one month.  Together

14. Example 2: A company comes up with a new fuel that will triple your gas mileage.  On your own

15. Billy Mays TV Commercials  Hypothesis?  Test??  Fix it Pro Fix it Pro Fix it Pro  Billy Mays Billy Mays Billy Mays

16.  Title- simple statement about what the graph shows  MUST have the independent and dependent variable Independent variable or Time : X axis Dependent variable: Y axis ****Don’t forget UNITS!!!!**** INDEPENDENT VARIABLE (X-AXIS) DEPENDENDENT VARIABLE (Y-AXIS)

17.  Scale: values on the x and y axis  Must increase by a CONSISTENT (repeating) value  Ex. by 5… 5 10 15 20 25 30  Ex. By 10… 10 20 30 40 50  Must FIT all data on the graph  Can’t draw in own lines to make graph larger  DO NOT DO THIS!!!!!:  Do NOT Use data as your scale  INSTEAD find Highest # and use CONSISTENT (repeating) value  Do NOT Draw a line to 0,0 if it is not in your data or draw lines further than data gives you  Do NOT Use a BREAK!!!

18. Example 1: 1.State one relationship between temperature and dissolved oxygen. 2. Predict the oxygen concentration at 35 degrees in freshwater.

19. COMMON MISTAKES 1.State one relationship between temperature and dissolved oxygen. 2. Predict the oxygen concentration at 35 degrees in freshwater.

20.  * 1cm = ___ mm

23. Measuring 1. What is this object?  What is something you have to do, to measure correctly? 2. Where do you measure from? (Draw it) 3. What is the volume?

24.  ** Find the Value of each _______ **

26. A tool that magnifies images to make them more detailed

27. Always carry with 2 hands Inform teacher if it is not working correctly Do not force knobs Remove Slide Always wrap cord back around microscope Put on correct shelf NEATLY when done

28. Eyepiece/ Ocular Nosepiece Arm Objective Lens Stage Stage Clips Coarse Adjustment Fine Adjustment Base Diaphragm Light

29. Microscope Parts and Functions OcularLook through & magnifies Objective LensesMagnifies, Scanning (4x), low (10x), high(40x) StageFlat surface where slide is placed DiaphragmControls amount of light Light SourceProvides the light Coarse AdjustmentQuickly changes focus, Used to focus under LOW POWER ONLY, larger knob Fine AdjustmentSharpens image, use under High and Low Power

30. Body Tube Nosepiece Objectives Stage Clips Light Ocular lens (Eyepiece) Arm Stage Coarse Adjustment Fine Adjustment Always carry a microscope with one hand holding the arm and one hand under the base. Base Diaphragm

31. Place the Slide on the stage Secure using stage clips? START in SCANNING(LOWEST) power Use the Coarse  Fine Adjustment

32. Center it Change to next power (Medium) Focus and CENTER it Change to HIGH POWER Do NOT use the Coarse Focusing Knob  (may damage slide or specimen) What can you find on your slide?

33. WHAT Do YOU SEE WHEN LOW  HIGH FIELD OF VIEW – Amt. of slide you can see High Power – Smaller field of view (see less of object) – in more DETAIL Low Power – Larger field of view, but smaller Which of these images would be viewed at a higher power of magnification?

34. What’s my power? To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective. What are the powers of magnification for each of the objectives we have on our microscopes?

35. The Compound Light Microscope Calculating total Magnification Ocular x objective = total magnification OcularObjectiveTotal 10x 20x 10x40x

36. The image will be upside-down and backwards

37. TO CENTER IMAGE - Always move SLIDE towards the image (and image will move opposite) Which way do I go? Organism swims toward upper right Move slide toward upper right

38. Measuring with Microscope Take total diameter and divide by estimated # of cells

39. How to make a wet-mount slide … 1 – Place ONE drop of water in the middle of the slide 2 – Place the edge of the cover slip on one side of the water drop. You do not need to use the stage clips when viewing wet-mount slides! 4 – **Reduces bubbles** 5. 3/4 - Slowly lower the cover slip at an angle Cover Slip Lower slowly

40. CHANGING SALT concentration(or adding a stain) w/out lifting coverslip ADD NEW SOLUTION TO ONE SIDE PUT A PIECE OF PAPER TOWEL TO THE OTHER SIDE  

41. E. COLI BACTERIA HEAD OF A SMALL BLACK ANT POLLEN