Fixation (II: Compound Fixatives)

Question 1

Fixation time for 10% formol-saline

Answer 1

12-24 hours

Question 2

For preservation of post-mortem surgical research specimens

Answer 2

10% buffered formalin

Question 3

Fixation time for 10% buffered formalin

Answer 3

24 hours or more

Question 4

For biopsies of the skin

Answer 4

Heidenhain’s Susa Solution

Question 5

Fixation time for Haidenhain’s Susa Solution

Answer 5

3-12 hours

Question 6

For routine post-mortem materials

Answer 6

Formol sublimate

Question 7

Fixation time for formol sublimate

Answer 7

3-24 hours

Question 8

Does not preserve thick slices of tissue; not to be used for than 1 cm thick sections

Answer 8

Formol sublimate

Question 9

For post-mortem materials

Answer 9

Formol saline sublimate

Zenker’s solution

Question 10

Recommended for tissues to be stained by one of the trichrome technique

Answer 10

Zenker’s solution

Question 11

For pituitary tissues and bone marrow

Answer 11

Zenker’s formol (Helly’s fluid)

Question 12

Prolonged fixation produces brown scum

Answer 12

Zenker’a formol (Hellyy’s fluid)

Question 13

For embryos and glycogen

Answer 13

Bouin’s solution

Question 14

Should never be used for preserving kidneys due to extreme distortion

Answer 14

Bouin’s solution

Question 15

Recommended for nuclear structures (chromosomes)

Answer 15

Flemming’s fluid

Question 16

Recommended for chromosome study, lymph nodes, and urgent studies for glycogen

Answer 16

Carnoy’s fluid

Question 17

Fixes and dehydrates simultaneously

Answer 17

Carnoy’s fluid

Question 18

Most rapid of all fixatives

Answer 18

Carnoy’s fluid

Question 19

Recommended for mucopolysaccharides, nuclear protein, and chromosomes

Answer 19

Newcomer’s fluid

Question 20

When using this fixative, tissues require only one change of absolute alcohol before clearing

Answer 20

Newcomer’s fluid

Question 21

Recommended for cytoplasmic structures

Answer 21

Flemming’s fluid (without acetic acid)

Question 22

For mitochondria, Golgi elements, and fats

Answer 22

Champy’s fluid

Question 23

For mitochondria and yolk

Answer 23

Regaud’s fluid (Moller)

Question 24

Needs post-chroming

Answer 24

Regaud’s fluid (Moller)

Question 25

More penetrating than chromium fixatives

Answer 25

Regaud's fluid (Moller)

Question 26

Recommended for study of early degenerative process and tissue necrosis

Answer 26

Orth's fluid

Question 27

Demonstrates Rickettsia and other bacteria

Answer 27

Orth's fluid

Question 28

Preserves myelin better than buffered formalin

Answer 28

Orth's fluid

Question 29

Recommended for materials from the nervous system and general post-mortem materials

Answer 29

10% Formol-saline