A- Rotating nosepiece
B- Ocular lens
C- Substage light
D- Head
E- Objective lens
F- Light control
G- Mechanical stage
H- Stage
I- Condenser
J- Arm
K- Coarse Adjustment Knob
L- Mechanical Stage Control
M- Iris Diapgrahm Lever
N- Fine Adjustment knob
o- Base
The proper technique for transporting the microscope
Hold it in an upright position with one hand on the arm and the other arm on the base
The microscope must be cleaned with
Special grit free lens paper (In a circular motion)
When beginning to focus the ____ power lens should be used.
Lowest power
When focusing, always focus ______ from the specimen
Away
(So the slide won't break)
use the Coarse Adjustment Knob only with the _____ power lens.
Lower- power lens
The platform on which the slide rests for viewing
Stage
The microscope structure
used to increase the amount of light passing through the specimen
Condenser
The microscope structure
that secure the slide to the stage
Mechanical Stage
The microscope structure
that delivers a concentrated beam of light to the specimen
Iris diaphragm
The microscope structure
used for precise focusing once initial focusing has been done
Fine Adjustment Knob
The microscope structure
that carries the objective lenses; rotates so that different objective lenses can be brought into position over the specimen
movable nose piece
The real image is magnified to produce the ______________ seen by your eye.
Virtual Image
Define Resolution
The ability to discriminate 2 close objects as separate (Resolving power)
The distance from the bottom of the objective lens to the specimen is ____________
Working distance
Assume there is an object on the left stage of the field that you want to bring to the center.
What direction would you move the slide?
Right
The area of the specimen seen when look through the microscope is _______
field
If a microscope has a 10x ocular and the total magnification at a particular time is 950x,
the object lens used at the time is ___x
95
[10x * 95= 950x]
Why should the light be dimmed when looking at the living cell?
To provide more contrast for viewing the lightly stained cells.
(Also, a wet mount can dry out by the heat from the light.)
If, after focusing in low power, only the Fine Adjustment need be used to focus the specimen at the higher powers, the microscope is said to be _______
Parfocal
Say, you are observing an object in the low- power field. When yo switch to high power, it is no longer in your field of view.
Why?
BECAUSE, In lower power you have a WIDER field of view.
When you switch to higher power, your view NARROWS, and becomes out of focus.
Lower power- Wider view
Higher power- Narrow view
How can you prevent it from happening?
Center the object as much as possible before switching to a higher power and increasing the magnification slowly.
Higher Magnification, Resolution (Increases/ Decreases)
increases
Higher magnification, Working distance (Increases/ Decreases)
Decreases
Higher magnification, Amount of light needed (Increases/ Decreases)
Increases
Higher Magnification, Depth of light (Increases/ Decreases)
Decreases
A higher lens is a high power, so it only needs a _______ workiing distance.
shorter (mm)
Probable situations arising in microscope:
-> Only half of the fields illuminated because....
-> Field does not change as mechanical stage is moved...
-> because there is a blockage in the light path
-> mechanical stage contacts between the specimen and the objective lens