microscope lab do now: pick up lab and preread the whole lab, answer pre-lab questions when finished...
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Microscope LabMicroscope Lab
Do Now: Pick up lab and preread the whole lab, answer pre-lab questions
when finished reading. Not before, after!
Do Now: Pick up lab and preread the whole lab, answer pre-lab questions
when finished reading. Not before, after!
Set up your Cornell Notes As Follows (skip lines……):Set up your Cornell Notes
As Follows (skip lines……): I. Safety II. Magnification III. Preparing Wet Mount IV. Focusing V. Electron Microscopes Define: resolving power, depth of
view
I. Safety II. Magnification III. Preparing Wet Mount IV. Focusing V. Electron Microscopes Define: resolving power, depth of
view
Compound Light Microscope
Compound Light Microscope
Always carry with 2 hands Arm and base
Place away from edge of table Always start with
stage all the way down Light off Lowest power
Always return the microscope to this position when finished
Always carry with 2 hands Arm and base
Place away from edge of table Always start with
stage all the way down Light off Lowest power
Always return the microscope to this position when finished
• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10• 11• 12• 13• 14• 15
• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10• 11• 12• 13• 14• 15
Eyepiece Course
FocusFine FocusScanning
ObjArm Power Body TubeNose piece High
PowerLow PowerClips Stage Diaphragm Light Base
Eyepiece Course
FocusFine FocusScanning
ObjArm Power Body TubeNose piece High
PowerLow PowerClips Stage Diaphragm Light Base
MagnificationMagnification• Eyepiece
– What you look through– May have pointer inside– 10x
• Rotating nosepiece has 3 objectives– Scanning (short and red) 4x– Low (medium and yellow) 10x– High (long and blue) 40 x
• Eyepiece– What you look through– May have pointer inside– 10x
• Rotating nosepiece has 3 objectives– Scanning (short and red) 4x– Low (medium and yellow) 10x– High (long and blue) 40 x
Total Magnification =Eyepiece X objectiveTotal Magnification =Eyepiece X objective
• Eyepiece• 10x
• Eyepiece• 10x
• Scanning 4x = 40x total• Low 10x = 100x total• High 40x = 400x total
• Scanning 4x = 40x total• Low 10x = 100x total• High 40x = 400x total
Controlling lightControlling light
• First plug in and turn on the light.
• Under the stage is a rotating disc that turns and clicks
• It may have numbers on it• Turning the diaphragm (disc)
controls the amount of light
• First plug in and turn on the light.
• Under the stage is a rotating disc that turns and clicks
• It may have numbers on it• Turning the diaphragm (disc)
controls the amount of light
Slide #1• Prepared slide of crossed threads
• Place slide on stage and secure• Use scanning objective and try to center the
crossed threads then focus– Use course focus (large knob) first– Fine focus (small knob) second– Which way does the slide move if you push it left? Push
right?– What affect does changing the diaphragm have on the
image?
• Change to low power– Notice any change?– Draw
• Change to high power– USE ONLY FINE FOCUS!– Course focus can press into slide and crack
the glass, squish specimen, and damage the objective.
– It may take time to focus correctly - practice– How does the view of the image change?– Draw
NO SQUISH THE SLIDE!!!!!!
The Wonderful Letter e• Preparing a wet-mount
– Cut out a lower case letter e– Place on slide– Carefully add water drop– Try to keep the e looking like this… e– Carefully place cover slip on letter
• Place slide on microscope and secure
• Start with scanning objective - center and focus. See any thing unusual?
• Change to low power and draw
• Change to high power and draw
Depth of View
• Notice that as you increase magnification you see more detail of less of the image.
• You also see layer of the image that you can focus through
• More of less
Resolving Power• A measure of the clarity of an image.
Closure• Complete post lab questions
• Turn in lab
Electron MicroscopeElectron Microscope
• Scanning or SEM• Uses electrons bounced
off the surface of the specimen
• Transmission or TEM• Electrons through the
specimen
• Live specimens cannot be used
• Scanning or SEM• Uses electrons bounced
off the surface of the specimen
• Transmission or TEM• Electrons through the
specimen
• Live specimens cannot be used
Electron Microscope (2 kinds)
Electron Microscope (2 kinds)
• *• *
Transmission Electron Microscope
Transmission Electron Microscope
• TEM-• Electrons go • Through the• Specimen• (non living • Specimens• Only)
• TEM-• Electrons go • Through the• Specimen• (non living • Specimens• Only)
Scanning Electron Microscope
Scanning Electron Microscope
• SEM –• Uses electrons• Bounced off the• Surface of the • Specimen• (non living• Specimens only)
• SEM –• Uses electrons• Bounced off the• Surface of the • Specimen• (non living• Specimens only)