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Purpose of Microscope
to see inside of organisms and cells;what is invisible to the naked eye
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Compound Microscope
- has two lenses at opposite ends of tube
- for smaller things
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Ocular Lens
- top
- 10x life size; what you look through
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Body Tube
- under the ocular lens
- connects arm to the ocular lens
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Revolving Nosepiece
- between objectives and body tube
- moves the objectives
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Objective Lens
- connected to the revolving nosepiece
- lens nearest object/specimen
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Stage
- under objective lens
- where specimen is placed
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Stage Clips
- on stage
- holds the microscope slide, keeps specimen in place
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Diaphragm
- below stage
- allows the light to pass through the stage
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Light Source
- on button of microscope
- source of light
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Light Switch
- back of microscope
- turns on light
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Coarse Adjustment Knob
- side of arm
- bring specimen to view
- used under low power, if used under high power can crack the slide
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Fine Adjustment Knob
- side of arm
- focus the view
- used to focus under high power
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Base
- bottom
- supports microscope
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Dissecting Microscope
- binocular= 2 ocular lenses; 3D
- for larger objects
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Magnification
measure of how big an object looks to your eye compared to life size
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Total Magnification
multiply the ocular lens(10x) by power of the objective lens
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Resolution/Resolving Power
- measure how clearly you can see details in the microscope
- is usually given as distance between two objects that can barely be resolved
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Field of View
gets smaller as magnification increases
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Point of Interest
- what you are looking at
- if it is not exactly centered in low magnification, will not be visible at higher magnifications
- if not visible, return to low power, center, switch to high power
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Depth of Field
- decreases as field of view becomes smaller
- thickness of specimen is larger under low power, easier to focus using coarse adjustment
- thin layer is in focus under higher magnification, use fine adjustment
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Microbes
- organisms too small to be seen in any detail with the naked eye
- 1 micrometer= 1/1000 of a millimeter
- human eye can see objects 100 micrometers or larger
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Measuring Objects
 - a= field size at 100x in mm
- b= low magnification(100x)
- c= size of the field you are trying to determine
- d= magnification of field you are trying to determine
- Ex) a=3mm b=100 c=? d=400x
compare size of object to size of field, if object is 1/4 of diameter of field
0.25* 750= 187.5 micrometers
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Transmission Electron Microscope
- can actually cut through
- can see "inside"
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Scanning Electron Microscope
- scans surface
- gives 3D appearance
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