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Question 1

Hematoxylin is not soluble in alcohol or water, but it is in _________

Answer 1

ethylene glycol

Question 2

Why is sodium iodate a preferred oxidant for Hx?

Answer 2

Oxidizes at RT

Question 3

T cell marker

Answer 3

CD3

Question 4

This dye is linear and stains beta pleated sheets

Answer 4

Congo red

Question 5

Oxidized product of hematoxylin and its charge

Answer 5

Hematein; negative

Question 6

3 anionic auxochromes

Answer 6

Sulphonic (SO3-)
Carboxylic (COO-)
Phenolic (O-)

Question 7

Why is NaOH added to Congo Red

Answer 7

Promotes hydrogen bonds

Question 8

What is over-oxidized hematoxylin called?

Answer 8

Oxyhematein or isohematein

Question 9

Consequence of prolonged decalcification on HandE staining?

Answer 9

Poor nuclear detail

Question 10

What is the charge on all dyes used in trichrome

Answer 10

Anionic

Question 11

Used to differentiate slides in Verhoeff’s

Answer 11

Ferric chloride

Question 12

2 fixatives that contain mercuric chloride

Answer 12

Zenker’s (Helly’s)

B5

Question 13

Trichrome - what does aniline blue stain

Answer 13

Collagen

Question 14

2 ways to make Hx more selective

Answer 14

• Add more acid

- Apply excess mordant

Question 15

Dye that stains keratin in PAP method

Answer 15

Orange G

Question 16

Stain that contains a very large positively charged molecule w/ copper in it

Answer 16

Alcian blue

Question 17

Anionic group involved in metachromasia

Answer 17

chromotrope

Question 18

Mordant:hx ratio

Answer 18

35:1

Question 19

Collagen found in basement membranes

Answer 19

Type IV

Question 20

Trichrome theory - larger dyes displace smaller dyes in collagen due to ______________

Answer 20

stronger bonding

Question 21

Oxidizing agent in Harris’ hematoxylin

Answer 21

Mercuric oxide

Question 22

Main disadvantage of using EDTA as a decalcifying agent?

Answer 22

Extremely slow

Question 23

This fixative requires the addition of formalin prior to use

Answer 23

B5

Question 24

Colour of hematein in low and high pH?

Answer 24

Low = red
High = blue

Question 25

Why cool blocks after embedding in molten wax?

Answer 25

Wax will form SMALLER cystals

Question 26

This tissue element should stain magenta-pink after PAS+D staining

Answer 26

Neutral sugars in colonic goblet cells

Question 27

Example of a modified leuco dye is found in this method

Answer 27

PAS

Question 28

2 types of carbohydrates that stain with Alcian blue

Answer 28

Proteoglycans and glycoproteins

Question 29

May be used to identify neutrophils in a smear or tissue section

Answer 29

Chloroacetate esterase

Question 30

Eosin has an overall _______ charge and is therefore referred to as an _________ dye (not cationic/anionic)

Answer 30

negative; acidic

Question 31

Main disadvantage to the use of paraffin wax as an embedding agent?

Answer 31

Limit to section thickness

Question 32

Dye that stains cytoplasm in PAP method

Answer 32

Eosin azure

Question 33

The iron hematoxylins made with ferric chloride have a very short shelf life because..?

Answer 33

the ferric chloride oxidizes hematein then to oxyhematein

Question 34

2 possible consequences of adding acid to dye solutions to promote ionization

Answer 34

- anionic dyes becoming un-ionizes | - dye precipitation

Question 35

Anhydrous copper sulphate is sometimes added to this to check for presence of water

Answer 35

ethanol (turns blue in presence of water)

Question 36

Best tissue for HandE control slide

Answer 36

GI tract

Question 37

What could cause freshly made eosin to precipitate

Answer 37

Too much acid

Question 38

Example of a neutral dye

Answer 38

Romanowsky-Giemsa

Question 39

Colourless dye in PAS?

Answer 39

Schiff's reagent

Question 40

Mast cells have __________ which allow metachromatic staining

Answer 40

chromotropes

Question 41

The usual temperature that wax baths are maintained at?

Answer 41

60 degC

Question 42

Oxidizing agent in Gill's hematoxylin

Answer 42

Sodium iodate

Question 43

A suitable marker for B lymphocytes could be

Answer 43

L26/CD20

Question 44

The major objection for the use of xylene as a clearing agent for processing tissues?

Answer 44

Xylene is likely to harden tissue