Dehydration, Clearing, Decalcification

Question 1

Removal of Ca+ ions or lime salts

Answer 1

Decalcification

Question 2

Ratio of fluid to tissue

Answer 2

20:1

Question 3

Optimal temperature for decalcification.

Answer 3

Room temp (18-30 deg. C)

Question 4

Most common decalcifying agent?

Answer 4

5-10% Nitric Acid

Question 5

Complete digestion of tissue with in 24-48hrs.

Answer 5

55 deg. C

Question 6

Most rapid method of decalcification.

Answer 6

Electrophoresis (Electrical Ionization)

Question 7

temp for nuclear w Van Gieson is impaired.

Answer 7

37 deg. C

Question 8

Duration of Ion Exchange Resin

Answer 8

1-14 days

Question 9

Specimen is placed in a container with the decalcifying acid with ammonium form of Polystrene Resin at the bottom of the container.

Answer 9

Ion exchange resin

Question 10

Processing time in using chelating agents with small pcs of bone.

Answer 10

1-3 weeks

Question 11

Processing time in use of chelating agents with large dense bone.

Answer 11

3-6 or 6-8 weeks

Question 12

What is the most commonly used and fastest decalcifying agent?

Answer 12

Nitric Acid

Question 13

Nitric acid imparts what color?

Answer 13

Yellow

Question 14

Recommended only for minute pieces of bones.

Answer 14

Hydrochloric acid

Question 15

Recommended for decalcifying cartilage, research specimens, autopsy specimen, bone marrow

Answer 15

Formic acid sodium citrate

Question 16

Weak and slow decalcifying agent

Answer 16

TCA / Sulfurous acid

Question 17

Also known as “Fleming’s Solution with Acetic Acid” that is not commonly used because it is considered as an environmental toxin. (highly corrosive on skin)

Answer 17

Chromic acid

Question 18

Contains chloroform as preservative.

Answer 18

Citric Acid Citrate Buffer

Question 19

T or F: Gentle agitation decrease rate of decalcification. Great access on the whole surface of the specimen can speed up rate of decalcification.

Answer 19

First statement is false. Second statement is True.

Question 20

Not a reliable method for testing the completeness of decal. despite its easy process.

Answer 20

Physical or Mechanical Method

Question 21

Method of testing for the completeness of decalcification that can detect even small amount of calcium; most reliable. Opaqueness is observed.

Answer 21

X-ray or Radiologic method

Question 22

Carried out by adding Calcium Carbonate; presence of bubble is not yet complete. Also the easiest method.

Answer 22

Bubble test

Question 23

Used tissue softeners for Lendrums Method

Answer 23

4% Aqueous Phenol (for 1-3 days)

Question 24

Decalcification is not mandatory. Dehydration is a mandatory step in tissue processing.

Answer 24

Both statements are true.

Question 25

It is the Removal of intercellular and extracellular water from tissues.

Answer 25

Dehydration

Question 26

For hard tissues (e.g. nails and tendons), what is added to alcohol bath?

Answer 26

4% phenol

Question 27

Dehydrating agent that is most common and best used; readily available, and is fast acting and non-toxic. Miscible with water.

Answer 27

Ethanol / Ethyl Alcohol

Question 28

Suited only for blood and tissue smears. Not commonly used because it's toxic; can cause blindness.

Answer 28

Methyl Alcohol

Question 29

Recommended for plant and animal microtechniques.

Answer 29

Butyl Alcohol

Question 30

Universal solvent; acts as dehydrating and clearing agent.

Answer 30

Tertiary Butyl Alcohol

Question 31

Excellent substitute for ethanol that is used for microwave technique. Used as xylene substitute in rapid automated tissue processing. Cannot be used in celloidin technique.

Answer 31

Isopropyl Alcohol (IPA)

Question 32

T or F: Pentanol (Amyl alcohol) is NOT miscible with water.

Answer 32

TRUE

Question 33

Used to diagnosed rabies/brain; urgent biopsies, because fast-acting. Can fix and dehydrate tissue.

Answer 33

Acetone

Question 34

Dehydrates and clear tissues, that is toxic when ingested or inhaled; has offensive odor and can cause skin and eye irritation.

Answer 34

Tetrahydrofuran (THF)

Question 35

Cellosolve. Combustible at 110-120 deg. F; toxic by ingestion, inhalation, and skin-contact.

Answer 35

Ethylene Glycol Monoethyl Ether

Question 36

Explodes upon exposure to air. Dehydrates and clear tissue; not commonly used. Finds to ribbon poorly.

Answer 36

Diethylene Dioxide (Dioxane)

Question 37

The removal of dehydrating agent from tissues.

Answer 37

Dealcoholization / Clearing

Question 38

T or F: Ethanol and wax are miscible with water. Wax cannot infiltrate the tissue if it still has ethanol.

Answer 38

Only the second statement is correct.

Question 39

Most common clearing agent but not suited for nervous tissues and lymph nodes. Clearing time is 15-30 mns.

Answer 39

Xylene (Xylol)

Question 40

Clearing agent that can cause Aplastic Anemia; highly flammable; suited for urgent biopsies. Clearing time is 15-60mns.

Answer 40

Benzene

Question 41

Can be used as a substitute for Xylene and Benzene; but not fast-acting compared to it. 1-2 hrs clearing time.

Answer 41

Toluene

Question 42

Recommended in clearing tough tissues, nervous tissues, lymph nodes, and embryos; but toxic to the liver. And does not make the tissue transparent.

Answer 42

Chloroform

Question 43

Recommended for clearing embryos, insects, and other delicate specimens.

Answer 43

Aniline oil

Question 44

Extremely slow clearing agent; 2-3 days.

Answer 44

Cedarwood oil

Question 45

Slow and weak clearing agent; tissues tend to become adulterated. Expensive.

Answer 45

Clove oil

Question 46

Similar properties with chloroform but cheaper.

Answer 46

Carbon Tetrachloride

Question 47

Used to clear eye specimens.

Answer 47

Terpineol

Question 48

Substitute for Xylene

Answer 48

N-butyl acetate

Question 49

natural oil obtained from citrus peels.

Answer 49

Limonene