Processing

Question 1

To speed up the laboratory processing of all surgical tissues, the temperature of all fixation, dehydration and clearing steps has been set at 45C. This will most likely result in:

a. excellent section of all tissue
b. very soft uterine scrapings
c. overprocessed biopsy tissue
d. sections that will not stain with eosin

Answer 1

c. overprocessed biopsy tissue

Question 2

One advantage of aliphatic hydrocarbons is that they:

a. have hight tolerance to water
b. are miscible with all mounting media
c. are low in toxicity and sensitization
d. are adaptable to various processing methods

Answer 2

c. are low in toxicity and sensitization

Question 3

Which of the following clearing agents is NOT flammable?
a. benzene 
b.chloroform 
c. toulene 
d .xyelene

Answer 3

b.chloroform

is volatile

Question 4

The ideal thickness of specimens to be decalcified is:

Answer 4

3-4 mm (grossing measurements for any tissue)

Question 5

Processing of delicate tissues (eg. embryonic tissues) should be started in what concentration of alcohols?

a. 30%
b. 50%
c. 70%
d. 90%

Answer 5

a. 30%

Question 6

what gas is released during decalcification?

Answer 6

CO2

Question 7

processed tissue that was fixed in zinc-formalin is very hard and brittle. The stained sections show microscopic chatter. This problem might be corrected in the future by:

a. leaving the tissue in the fixative for less than 4hrs
b. treating the tissue for removal of pigment
c. placing the tissue in a buffer solution after fixation
d. selecting a better schedule for processing

Answer 7

d. selecting a better schedule for processing

zinc formalin does not cause formation of salts

Question 8

Microscopic review of H&E section of a colon bx show very uneven staining of the tissue and poor nuclear detail. The cause is:

a. paraffin block was cooled too slowly
b. tissue remained in alcohol too long
c. pH of the fixative was incorrect
d. clearing agent is contaminated with water

Answer 8

d. clearing agent is contaminated with water

Question 9

To help preserve membranes in frozen section, prior to freezing fixed tissue may be places in a solution of: a. gum mastic

b. saline
c. sucrose
d. talc

Answer 9

c.sucrose

Question 10

The penetration of any solution into tissue is increased as which of the followings is increased?

a. molecular size of the solution
b. temperature of the solution
c. viscosity of the solution
d. specific gravity of the solution

Answer 10

b.temperature of the solution

Question 11

An alcohol is a compound in which one or more of the hydrogen atoms of a hydrocarbon has been replaced by which of the following groups?

a. hydroxyl
b. keton e
c. methyl
d. carboxyl

Answer 11

a. hydroxyl

Question 12

if a laboratory ran out of ethanol, what dehydrant might be available and suitable for emergency use?

Answer 12

isopropanol

Question 13

embedding orientation for LIPOMA

Answer 13

LIpoma= homogeneous sp of fatty tissue w/out clear edges

• embedded so that the greatest surface area can be viewed on sections