Natural dyes

Question 1

natural dye derived by extraction from the core or the
heartwood of a Mexican tree known as “Hematoxylin Campechianum”.

Answer 1

Hematoxylin

Question 2

T/F.
Hematoxylin itself is not a true basic dye

Answer 2

True

Question 3

active coloring agent of Hematoxylin

Answer 3

Hematin

Question 4

formed by the oxidation of hematoxylin, a process known as “ripening.”

Answer 4

Hematin

Question 5

Ripening takes as long as

Answer 5

3-4 months

Question 6

Ripening can be accelerated by adding strong oxidizing agents such as

Answer 6

• hydrogen peroxide
• mercuric oxide
• potassium permanganate
• sodium perborate
• sodium iodate

Question 7

excessive oxidation (over-ripening) leads to production of other

Answer 7

useless substances

Question 8

T/F.
Using the least amount of oxidant will result in satisfactory staining and longer life of the stain.

Answer 8

True

Question 9

seldom used alone due to its inherent low affinity for the tissue itself

Answer 9

Ripened Hematoxylin

Question 10

Ripened Hematoxylin is most frequently used in combination with

Answer 10

• alum
• iron
• chromium
• copper salts

Question 11

alum, iron, chromium and copper salts acts as

Answer 11

Mordant

Question 12

substances that combine with the tissue and the staining solution, forming a “bridge” that allows staining reaction to take place.

Answer 12

Mordant

Question 13

recommended for progressive staining of
tissues, and are usually counterstained with Eosin, Congo Red and Safranin.

Answer 13

Alum hematoxylin stains

Question 14

Stains that contains Alum hematoxylin

Answer 14

• Ehrlich’s solution
• Harris’solution

Question 15

Rapid ripening of Ehrlich’s reagent is brought about by the addition of

Answer 15

Sodium Iodate

Question 16

Rapid ripening of Harris solution is brought about by the addition of

Answer 16

Mercuric Chloride

Question 17

used only for differential or regressive staining

Answer 17

Iron hematoxylin compounds

Question 18

differentiating agent used in Iron hematoxylin compounds

Answer 18

Acid-Alcohol

Question 19

example of an IRON HEMATOXYLIN COMPOUND is

Answer 19

Weigert’s Stain

Question 20

Weigert’s Stain uses

Answer 20

Iron (Ferric) Chloride

Question 21

utilized for the study of spermatogenesis

Answer 21

Copper hematoxylin solutions

Question 22

used frequently in histology to examine thin sections of tissue

Answer 22

Hematoxylin and eosin (H&E)

Question 23

stains cell nuclei blue

Answer 23

Hematoxylin

Question 24

stains cytoplasm, connective tissue and other extracellular substances pink or red

Answer 24

eosin

Question 25

T/F.
H & E preparation the red blood cells are almost
orange

Answer 25

True

Question 26

T/F.
collagen and cytoplasm (especially muscle) acquire different shades of pink

Answer 26

True

Question 27

old histologic dye extracted from the female cochineal
bug (Coccus Cacti)

Answer 27

Cochineal dye

Question 28

Cochineal dye treated with alum to produce the dye

Answer 28

carmine

Question 29

T/F.
Cochineal dye is widely used as a powerful chromatin and nuclear stain for fresh material and smear preparations

Answer 29

True

Question 30

Cochineal dye combined with picric acid

Answer 30

(picrocarmine)

Question 31

(picrocarmine) is for

Answer 31

neuropathological studies

Question 32

Cochineal dye combined with aluminum chloride

Answer 32

(Best’s carmine stain)

Question 33

(Best’s carmine stain) is for

Answer 33

glycogen

Question 34

vegetable dye extracted from certain lichens

Answer 34

Orcein

Question 35

Orcein is normaly appears

Answer 35

colorless

Question 36

Orcein treated with ammonia and exposed to air,
produces

Answer 36

blue or violet colors

Question 37

T/F.
Orcein is a weak acid, is soluble in alkali, and is
mainly used for staining ELASTIC FIBERS.

Answer 37

True

Question 38

also obtained from lichens, treated with lime and soda, and exposed to ammonia and air

Answer 38

Litmus

Question 39

T/F.
Litmus is not used as a cytological stain because of its poor staining property. used mainly as an indicator.

Answer 39

True