T. Tomm Updated 2015 http://sciencespot.net/ Images from http://www.tnmanning.com/id150.htm If your worksheet is completed, get a sticker from a helper. You may check your answers and fix anything you missed. If it is NOT done, you need to close your notebook and listen as we go over the answers. You will need to finish it before you will be allowed to use the microscopes. 1
Site #1: Microscope Diagram Body Tube Holds the objective lenses; can be rotated to change MAGNIFICATION Nosepiece Objectives Lenses that range from 4X to 40X HOLDS the slide in place Stage Clips Diaphragm Regulates the AMOUNT of light Light Source Provides the light needed to VIEW the specimen Eyepiece Also called the OCULAR lens Arm SUPPORTS the slide being viewed Stage Coarse Adjustment Knobs used to FOCUS the view Fine Adjustment Base Always carry a microscope with one hand holding the ARM and one hand under the BASE. Site #2: Virtual Electron Microscope Blood cells #1 - #6 - House Spider Eyes #2 - #7 - Skeletal Muscle #3 - #8 - Housefly Mouth #4 - #9 - Bone Cell Human Hair Immune System Cell Insect Spiracle Daisy Anther Mold #5 - #10 - Did your samples mess up? Write the correct #s next to each item. 2
Site #1: PBS Microscopes 1. Follow the directions to set up your first slide using the ONION ROOT. 2. What is the power of magnification for each objective? 4 10 40 Low = X Medium = X High = X 3. How do you figure the total magnification? Multiply the power of the OBJECTIVE by the power of the EYEPIECE X X 10 X 4. What is the total magnification for each power? 40 100 400 Low = X Medium = X High = X 5. Which is larger: coarse adjustment knob or fine adjustment knob? 6. Click the STOP button to proceed and follow the directions to use the microscope. You will have to focus the image to learn more about your sample. Nucleus or Nuclei 7. What are the purple circles? Cell walls What are the blue lines? Coarse 3
HIGH 8. At which power do you see the most detail of the individual cells? LOW 9. At which power do you see more cells (larger view of the entire sample)? LOW MEDIUM What is this? HIGH We can see better details with higher 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? 4
How accurate are your drawings of the specimens? Blood Cells LOW MEDIUM HIGH Bone Cells Let s look at a few prepared slides Glue on page 18 FAF Left SPECIMEN - Place the slide on the STAGE and CENTER what you want to see over the opening. LOW Always start with the LOW power objective (red-banded, shortest) and make sure it is CLICKED into place (pointing straight DOWN). ADJUSTMENTS Use the COARSE adjustment knob (big) to get your specimen in to view. Use the FINE (little) adjustment knob (little) to focus so you can see details. If you don t see anything, you may need to move the slide so the center of the specimen lines up with the end of the black POINTER. ROTATE - Once you see the image in low power, you can rotate the NOSEPIECE use the MEDIUM and HIGH powered objectives. Be careful with the HIGH POWERED objective (longest one). It may be hard to FOCUS or is too long to fit in the space. Don t force it into PLACE! 5
2. View the prepared slides available and choose THREE to document for this activity. DRAW what you see at each power the best you can! If you cannot view anything at the highest power, write UNABLE TO VIEW in that circle don t leave it blank! Be careful with the HIGH POWERED (longest) objective. It may be hard to focus or is too long. Don t force it into place! Done drawing your prepared slides? 1 You may view other prepared slides. 2 You may work on your Legends of Learning playlists. 3 You may work on homework from another class or read a book. We will start pond water samples on Monday. Have some good pictures? Rename them to let me know what it is. Upload it to the Microscope Pictures folder in Bug Blitz on Drive. 6
HOW TO MAKE A WET-MOUNT SLIDE Get a clean slide and coverslip from your teacher. 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! Place the edge of the cover slip on one side of the water drop. Slowly lower the cover slip on top of the drop. Place the slide on the stage and use low power to view it first. Once you see the image, you can rotate the nosepiece to view the slide with medium power objective. Do not use HIGH power with wet-mount slides. You do not need to use the stage clips when viewing wet-mount slides! You will want to be able to move the slide around. Pond Water Organisms Seed Shrimp (Ostracod) Water Flea Nematodes Rotifers (Watch for currents ) Dragonfly Nymph Use the picture guides or a Pond Water book to help you identify the critters you see! 7
ADD TO NOTES Terms to know Phytoplankton = Microscopic plant life Zooplankton = Microscopic animal life A few things to remember 1 Only use the RED banded and YELLOW banded objectives with pond water. 2 Place the slide on the stage and move the stage clips out of the way. Use the BIG KNOB to get it into view and then the SMALL KNOB to make it clearer. 3 - It is better to look at 10 little drops rather than 1 big drop. 4 Document at least 4 DIFFERENT ORGANISMS. Use the Pond Water guides and pictures to help you identify what you see. 5 CLEAN UP when you are done (or at the end of class)! Turn off microscope Use a paper towel to dry off the slide and cover slip. Put both on the tray with the dry paper towels. CARRY WITH 2 HANDS ONE ON THE ARM AND ONE ON THE BASE! 8
Done drawing your pond water organisms? 1 You may try to find other organisms. 2 You may work on Legends of Learning, homework from another class, or read a book. 9