2MICROSCOPES MAGNIFIES OBJECTS (MAKES OBJECTS LOOK BIGGER) HELP SCIENTISTS STUDY OBJECTS & LIVING THINGS TOO SMALL TO SEE WITH THE NAKED EYE
3Ocular lens (Eyepiece) Body TubeNosepieceArmObjectivesStageStage ClipsCoarse AdjustmentDiaphragmFine AdjustmentLightAlways carry a microscope with one hand holding the arm and one hand under the base.Base
43 Types of Microscopessimple microscope has only 1 lens. compound microscope has 2 sets of lenses. It can magnify things times larger than they really are.electron microscope can magnify objects up to 300,000 times. They do not use lenses, but use electrons to enlarge the image.
5PARTS OF A MICROSCOPE ocular (lens) eyepiece the lens of the microscope that you look throughcourse adjustmentthe large knob on the microscope that you turn to bring the object into focusfine adjustmentthe small knob on the microscope that brings the image into focus
6PARTS OF A MICROSCOPE arm body tube nosepiece the part of the microscope supporting the body tubebody tubethe part that holds the eyepiece and the objective lenses.nosepiecethe part at the bottom of the body tube that holds the objective lenses and allows them to be turned
7high power objective lens the lens that magnifies the object the greatest amount. (usually 40x)Low power (scanner) objective lensthe lens that magnifies the object the least amount (usually used to find the object; magnifies only 3x or 4x)middle power objective lensthe lens that usually magnifies the object more than the scanner lens, but less than the high power lens (usually 10x to 20x)
810. stagethe flat part below the objectives lens where the slide is placed11. clipthe part that holds the slide in place so it doesn’t move12. diaphragmthe part that controls the amount of light entering the field of view
913. light sourcethe lamp (or mirror) under the stage that sends light through the object being viewed.14. basethe bottom part that supports the rest of the microscope
10Ocular lens (Eyepiece) Body TubeNosepieceArmObjectivesStageStage ClipsCoarse AdjustmentDiaphragmFine AdjustmentLightAlways carry a microscope with one hand holding the arm and one hand under the base.Base
11Field of ViewField of view is the area (circle) that you see when looking through the eyepiece
12Comparing 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?
13Fill in the table on your worksheet. 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?Fill in the table on your worksheet.
14Calculating Magnification 1. Find the power of the lens. It is found on the side of the lens. Magnification power of a lens is always identified by the label of x (10x, 1000x)2. Multiply the power of the eyepiece by the power of the objective lens.3. Examples:eyepiece obj. lens10x times x10x times x10x times x
15Appearance of the Specimen Objects appear upside-down & backwardMovement appears to be in opposite direction than actual movementmove slideslide appears to move
16Let’s give it a try ...1 – Turn on the microscope and then rotate the nosepiece to click the red-banded objective into place.2 – Place a slide on the stage and secure it using the stage clips. Use the coarse adjustment knob (large knob) to get it the image into view and then use the fine adjustment knob (small knob) to make it clearer.3 – Once you have the image in view, rotate the nosepiece to view it under different powers. Draw what you see on your worksheet!Be careful with the largest objective! Sometimes there is not enough room and you will not be able to use it!4 – When you are done, turn off the microscope and put up the slides you used.
17Recording Observations Draw specimen large enough to fill “field of view” circleDraw as many details as possibleDrawing should be neatLabel specimenLabel power of magnificationName & date on paper
18Making a Wet Mount Slide 1. Use dropper to place a drop of water on the center of a clean slide.2. Use tweezers to lay specimen on the drop of water.3. Gently touch the cover slip to the edge of the drop of water to cover the specimen & the water.
19You do not need to use the stage clips when viewing wet-mount slides! How to make a wet-mount slide …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.4 - Slowly lower the cover slip on top of the drop.Cover SlipLower slowlyYou do not need to use the stage clips when viewing wet-mount slides!5 – Place the slide on the stage and view it first with the red-banded objective. Once you see the image, you can rotate the nosepiece to view the slide with the different objectives.