ASCP Tissue Processing 3

Question 1

Which reagent is used for decalcification of bone specimens?

Accepted Answer

EDTA or nitric acid

Answer

Acetic acid

Answer

Hydrochloric acid only

Answer

Xylene

Question 2

What is the consequence of over-decalcification on tissue?

Accepted Answer

Loss of nuclear staining and tissue damage

Answer

Improved section quality

Answer

Better paraffin infiltration

Answer

Increased tissue thickness

Question 3

A tissue block shows a grainy, washed-out appearance after H&E staining. What processing artifact is most likely responsible?

Accepted Answer

Under-fixation

Answer

Over-dehydration

Answer

Inadequate clearing

Answer

Paraffin over-infiltration

Question 4

What is the purpose of the post-fixation step using osmium tetroxide in electron microscopy preparation?

Accepted Answer

Fixation of lipids and enhancement of contrast

Answer

Dehydration of tissue

Answer

Decalcification of bone

Answer

Clearing of aldehydes

Question 5

Which endpoint test is used to determine if decalcification is complete?

Accepted Answer

X-ray examination or chemical endpoint test

Answer

Congo red staining

Answer

Gram stain

Answer

pH indicator strips only

Question 6

What tissue processing problem is indicated by a crumbly, brittle paraffin block?

Accepted Answer

Over-processing (over-dehydration or excessive paraffin heat)

Answer

Incomplete dehydration

Answer

Under-fixation

Answer

Insufficient paraffin infiltration