Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
The ability of an objective to separate objects which come very close together are called
|
Resolution or Resolving power
|
|
|
What is the standard limit of resolution?
|
0.2 micrometers (the distance 2 structures can be apart and you can still see them)
|
|
|
When too much light is used under low power, what happens to the stained bacterial specimen?
|
You are unable to focus on the specimen
|
|
|
What is the specific function of immersion oil?
|
The oil will trap light rays so they will not be refracted away from the objective. (immersion oil has the same refractive index as glass)
|
|
|
What limits the resolving power of the compound light microscope?
|
Dirty Lens
Condenser not in the highest position Diaphragm not not fully open |
|
|
Why increase the amount of light projected through the specimen under an oil immersion objective?
|
To obtain maximum resolution
|
|
|
Define: A simple Microscope
|
contains a single magnifying lens and a few working parts. eg; magnifying glass, a hand lens & Leeuwenhoek's basic little tool
|
|
|
Define: A compound Microscope
|
relies on 2 lenses that work together; the objective lens & the ocular lens that compound the image
|
|
|
How would you determine the total magnification of a compound microscope having a 6x ocular and a 30x objective?
|
ocular, 6x x objective, 30x = 180x
|
|
|
What is the function of the condenser?
|
it intensifies light directed on to the specimen
|
|
|
What is the function of the iris diaphragm?
|
it controls the amount of light which enters the condenser
|
|
|
What is the function of the fine adjustment knob?
|
located outward from the coarse adjustment knob, it independently & invisibly raises or lowers the objectives
|
|
|
What is the function of the coarse adjustment knob?
|
located close to the arm, visibly raises or lowers objectives
|
|
|
What is the function of the revolving nose piece?
|
it moves the objectives in to position over the specimen
|
|
|
What is the function of the stage knobs?
|
they move the stage horizontally North, South, East or West
|
|
|
Why is a low power objective used at the beginning of all slide examinations?
|
because it has a long working distance which eliminates contact between the lens and the slide
|
|
|
Name 2 Sciences besides microbiology where a microscope is a most useful tool.
|
Nanotechnology
Chemistry Physicists |
|
|
What is the specific use of a Dark-Field Microscope?
|
it is best for observing live, unstained specimens, specimen is bright, field is black, provides outline of specimen w/reduced internal cellular detail
|
|
|
What is the specific use of a Fluorescent Microscope?
|
specimens stained w/fluorescent dyes or combined w/fluorescent antibodies emit visible light; specificity makes this microscope an excellent diagnostic tool.
|
|
|
What is the specific use of a Phase-Contrast Microscope?
|
used for live specimens; specimen is contrasted against gray background; excellent for internal cellular detail
|
