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Histology Exam 1 > Microscopy > Flashcards

Flashcards in Microscopy Deck (19):
1

7 types of artifacts

1. swelling of tissue components
2. shrinkage of tissue components
3. wrinkles in section
4. tears in section
5. air bubbles
6. dust
7. stain precipitate

2

a measure of the ability to distinguish two points as town points

resolution

3

measures to what extent the light that passes through a specimen is spread out over and collected by the objective lens

numerical aperture (NA)
- allows us to calculate the resolving power of the objective

4

NA=

n x sin(a)

5

R =

0.61 X(lamda/NA)

6

the maximum useful magnification on a compound light microscope is between _______ and ____

1000X and 1500X

7

study of chemical nature of cells and tissues with the light and electron microscopes

histochemistry

8

forms a reaction product with degraded hemoglobin

perl reaction

9

study the role of calcium salts in bone histogenesis

Von Kossa method

10

lipid specific stain

sudan IV, sudan black

11

one facet of histological technique as being the most important or the potentially most useful technique

immunocytochemistry

12

Why fix tissue?

preserve structure
deactivates enzymes that would digest the tissue
make look like its living
never be the same so choose the fixative that will do the best job

13

why dehydrate fixed tissue ?

fixatives are water soluble, most embedding material is non polar and non miscible with water.

14

why embed?

tissue needs to be sectioned, so needs to be sturdy enough to withstand sectioning
want components to stay in natural positions and not move around (wax or plastic)
allows it to be but thin(7 micro meters for wax)

15

why section?

allows you to see internal structure
allows stains to easily get into tissue
allows light to pass through

16

why stain tissue?

creates higher contrast

17

tissue/cellular structures that are "created" by preparative techniques for histological specimens are called

artifacts

18

resolution of a microscope depends on

physical properties
of lenses
substance its in
b/t the specimen and lens
radiation used to image the specimen

19

look at the 5 criteria for histochemical reactions

look at the 5 criteria for histochemical reactions