HT Histology Techniques & Technology 3

Question 1

What is the role of a mordant in histological staining?

Accepted Answer

To link the dye to the tissue component

Answer

A mordant forms a bridge between the dye and the tissue, creating a stable dye–mordant–tissue complex and intensifying the stain.

Question 2

In the Masson trichrome stain, collagen fibers are demonstrated in which color?

Accepted Answer

Blue or green

Answer

Masson trichrome stains collagen blue (with aniline blue) or green (with light green), while muscle stains red and nuclei stain black.

Question 3

Which stain is the gold standard for demonstrating amyloid deposits in tissue sections?

Accepted Answer

Congo red

Answer

Congo red stains amyloid salmon-pink and shows apple-green birefringence under polarized light, which is pathognomonic for amyloid.

Question 4

The Prussian blue (Perls') reaction is used to detect which substance in tissue?

Accepted Answer

Ferric iron (hemosiderin)

Answer

Perls' Prussian blue reaction converts ferric iron to ferric ferrocyanide, producing a bright blue precipitate that identifies hemosiderin deposits.

Question 5

Diastase pre-treatment before PAS staining is used to confirm the identity of which tissue component?

Accepted Answer

Glycogen

Answer

Diastase (amylase) digests glycogen; PAS-positive material that disappears after diastase pre-treatment is confirmed as glycogen.

(HT) Histotechnician Certification Practice Test