The Microscope
Light Microscope
Microscope Rules
Microscope Rules: Always carry the microscope with two hands - one on the arm and one underneath the base of the microscope. Do not touch the lenses. If using a microscope with a light, turn off light when not in use.
Microscope Rules: Notify teacher if a slide or cover slip breaks. Always clean slides and microscope when finished.
Microscope Parts: A) Ocular/Eyepiece – used to look through, magnifies at 10X B) Objective Lenses – more magnification 1) Scanning – magnifies 4x 2) Low Power – magnifies 10x 3) High Power – magnifies 40x
Microscope Parts: C) Stage – platform which you mount slide D) Diaphragm – regulates the amount of light reaching the image E) Base – supports scope
Microscope Parts: F) Fine Adjustment (small knob)– used for final focusing, may be used with all 3 objectives G) Coarse Adjustment (large knob) – used for rough focusing – Used only with scanning and low power!! Moves stage.
Microscope Parts: H) Stage Clips – holds slide in place I) Arm – helps support scope J) Light – allows you to see object
Light Microscope
Total Magnification Total = Eyepiece x Objective Magnification Magnification Magnification
Magnification: 400x 40x 100x Magnification Ocular Lens Total Magnification Scanning 4x 10x Low Power High Power 40x 40x 100x 400x
Additional Notes Resolution – ability to see images that are closer together as separate Watch: YouTube - Pixel Commercial as it relates to Resolution Centrifuge – spins at high speeds and separates materials based on density Electron Microscope – allows the view of the internal structure of a cell Dissecting Microscope – allows you to study large specimens that cannot be easily seen with a compound light microscope
Focusing
Focusing Specimens: Always start with the scanning objective. Use the Coarse Knob to focus, image may be small at this magnification, but you won't be able to find it on the higher powers without this first step. Do not use stage clips, try moving the slide around until you find something.
Focusing: Once you've focused on Scanning, switch to Low Power. Use the Coarse Knob to refocus. Again, if you haven't focused on this level, you will not be able to move to the next level.
Focusing: Now switch to High Power. At this point, ONLY use the Fine Adjustment Knob to focus specimens.
Focusing: If the specimen is too light or too dark, try adjusting the diaphragm.
Images viewed under the light microscope are reversed (backward) and inverted (upside down).
Wet Mounts
Making a Wet Mount Gather a thin slice/piece of whatever your specimen is. Place ONE drop of water directly over the specimen.
Wet Mount: Place the coverslip at a 45o angle with one edge touching the water drop and then gently let go.
Staining
How to Stain a Slide: Place ONE drop of stain (iodine, methylene blue) on the edge of the coverslip. Place the flat edge of a piece of paper towel on the opposite side of the coverslip. The paper towel will draw the water out from under the coverslip, and the cohesion of water will draw the stain under the slide.
Staining… As soon as the stain has covered the area containing the specimen, you are finished. Watch: How to Make a Wet Mount/Stain A slide
Rules to Graphing 1) ALWAYS start with 0, unless they start the numbers for you OR if they use years. 2) BE CONSECUTIVE!! 0, 1, 2, 3, 4, 0, 2,4,6,8, 10 0, 5, 10 ,15, 20 0, 20, 40, 60, 80
3) NO BREAKS IN GRAPHS!!! (lightening bolt) 4) Use vertical bars for bar graph, or connect and circle all points in a line graph (first through last)
The End