all about scopes. labeling a microscope body tube revolving nosepiece objective stage clips...
TRANSCRIPT
Labeling A Microscope
Body Tube
Revolving Nosepiece
Objective
Stage Clips
Diaphragm
Light Source
Ocular Lens
Arm
Stage
Course Adjustment KnobFine Adjustment Knob
Base
What Do These Parts Do?
• Ocular lens – magnifies the image 10x
• Coarse adjustment – used for rough focus (use with LOW power)
• Fine adjustment – used for small movements in the magnification (use with HIGH power)
What Do These Parts Do?• Objectives – Used for enlarging the
image (scanning, low & high)
• Arm – used for carrying the microscope
• Stage – platform for holding the slide
What Do These Parts Do?
• Light source – provides light to see image
• Base – used for carrying the microscope
Total Magnification
• To find the total magnification:– Ocular lens x objective =
total magnification– 10 x (4) = 40
Ocular
Lens
Objective
Lens
Total
Magnification
a. 15x 15x 225
b. 10x 10x 100
c. 20x 40x 600
Microscope Image
• What you see on the stage is different from what you view when you look in a microscope– The image is reversed and inverted– This means it’s upside down and flipped
On the Stage Through The Scope
Finding FOV
• How far across is your field of view?
• PROCEDURE– Take clear ruler, put it under your
microscope and measure the FOV in mm across
1.3 cm
Staining Specimens
• Very frequently it is helpful to dye certain cell structures so that they can be seen more clearly.
• Chemicals that dye parts of cells for this purpose are called stains.
Staining Specimens1. A specimen is obtained and placed on
the slide.
2. The student then places a drop or two of water on the specimen.
3. A cover slip is then lowered on to the specimen from an approximately 45 degree angle gently.
• *This reduces the number of air bubbles the specimen will have.
Staining Specimens
Staining Specimens
4. The student places a drop of stain beside and under one corner of the cover slip
Staining Specimens5. The student places a towel on the opposite side of the cover slip in the water beside the cover slip. * This will draw the stain through the entire specimen in a few seconds without removing the cover slip. •This technique will also remove any air bubbles which
have formed.
6. The stained specimen may now be observed.
Staining Specimens
• Two commonly used stains in the biology laboratory:
• Lugol's iodine solution • Methylene blue
Staining Specimens
• Lugol's solution is a good stain to make the nuclei of plant cells stand out more prominently. It has the unfortunate drawback of killing the cells it used on however.