1. Life Science Mrs. Morgan

2. 2 One of the most important tools used to study living things. “Micro” means very small “Scope” means to look at

3. 1590 –first compound microscope

4. Lived in England in the 1600’s Used a compound microscope to look at cork From this cork he coined the term cells, as the cork looked like monastery quarters.

5. Used simple light microscope Was first to see live microscopic organism in pond water Lived in 1600’s

6. Types of Microscopes: 1.Compound Light Microscope (what we use most often) 2.Stereomicroscopes – also known as dissecting scopes 3. Electron Microscopes

8. Ocular lens Objective lenses

13. Parts of the Microscope a. Eyepiece Where you look into the microscope b. Nosepiece Holds the objective lenses (can be turned to increase magnification)

14. Parts of the Microscope c. Objective Lenses Increase magnification (usually from 10x to 40x) d. Stage Clips 2 clips that hold the slide in place

15. Parts of the Microscope e. Aperture Allows the light to pass through to the specimen you are viewing f. Stage Where the object you are looking at is placed.

16. Parts of the Microscope g. Diaphragm Changes the amount of light reaching the objective lenses. (Located under the stage; turn to let more light in or to make dimmer) i. Base Bottom part of the microscope that holds it up.

17. Parts of the Microscope j. Mirror or Lamp Sends light towards the aperature in the stage. (Mirror- move it to reflect the light) k. Arm Supports the body tube. Used to carry the microscope.

18. Parts of the Microscope l. Fine adjustment knob Use this to fine tune the image m. Coarse adjustment knob Moves the stage up and down (always begin with this one to focus)

19. Parts of the Microscope n. Body tube The hollow tube through which light passes. (Holds the objective and eyepiece lenses at the proper distance)

20. Practice Labeling the Parts

21. 1. To carry the microscope, grasp the ARM with one hand. Hold the BASE with your other hand. 2. Plug the microscope into the outlet. 3. Rotate the nosepiece so it is on the low power OBJECTIVE LENS. Using the Microscope in 10 Steps

22. 4. Place the slide on the STAGE. 5. Center the SPECIMEN over the APERTURE. 6. Secure the slide with the STAGE CLIPS.

23. 7. While looking at the STAGE from the side, turn the COURSE ADJUSTMENT KNOB ( the bigger one) to raise the STAGE until the LOW POWER OBJECTIVE_LENS almost touches the slide.

24. 8. Turn the light on and move the DIAPHRAGM so the largest hole is directly under the APERTURE. 9. While looking through the EYEPIECE, carefully move the COURSE_ADJUSTMENT KNOB until the specimen comes into view. If the specimen is not clear, use the FINE ADJUSTMENT KNOB ( the smaller one) until the specimen comes into focus.

25. 10. To switch to the HIGH POWER OBJECTIVE LENS look at the microscope from the side (to make sure not to hit the slide) and move the NOSEPIECE until the HIGH POWER OBJECTIVE LENS “clicks” into place. Turn the FINE ADJUSTMENT KNOB until the specimen comes into focus.

26. Remember to ALWAYS focus first with the COARSE ADJUSTMENT KNOB and then use the FINE ADJUSTMENT KNOB to make the image clearer. Don’t use the Coarse Adjustment Knob on high magnification (it will break the slide)

27. Occasionally you may have trouble with working your microscope. Here are some common problems and solutions. 1. Image is too dark! Adjust the diaphragm, make sure your light is on. 2. There's a spot in my viewing field, even when I move the slide the spot stays in the same place! Your lens is dirty. Use lens paper, and only lens paper to carefully clean the objective and ocular lens. The ocular lens can be removed to clean the inside. The spot is probably a spec of dust. 3. I can't see anything under high power! Remember the steps, if you can't focus under scanning and then low power, you won't be able to focus anything under high power. Start at scanning and walk through the steps again. 4. Only half of my viewing field is lit, it looks like there's a half- moon in there! You probably don't have your objective fully clicked into place.. Troubleshooting

28. What’s my power? To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective. Eyepiece lens- 10x Objective lens- 40x 10 x 40= 400x The object is 400 times “larger”

29. Comparing Powers of Magnification We can see better details with higher the powers of magnification, but we cannot see as much of the image. Which of these images would be viewed at a higher power of magnification?

30. How to make a wet-mount slide (dirty pond water)… 1 – Get a clean slide and coverslip from your teacher. 2 – Place ONE drop of water in the middle of the slide. Don’t use too much or the water will run off the edge and make a mess! 3 – Place the edge of the cover slip on one side of the water drop. 5 – Place the slide on the stage and view it first with the low objective lens. Once you see the image, you can rotate the nosepiece to view the slide with the different objectives. 4 - Slowly lower the cover slip on top of the drop. Cover Slip Lower slowly

31. Quiz Over the Microscope 1. When focusing a specimen, you should always start with the ___________________ objective. 2. When using the high power objective, only the ________ ___________ knob should be used. 3. The type of microscope used in most science classes is the _________________ microscope 4. What part of the microscope can adjust the amount of light that hits the slide? ______________________________

32. 5. You should carry the microscope by the ________ and the __________. 6. The objectives are attached to what part of the microscope (it can be rotated to click the lenses into place): _______________ ________________ 7. You should always store you microscope with the ________________ objective in place. 8. A microscope has an ocular objective of 10x and a high power objective of 50x. What is this microscope's total magnification? ____________