Histology Lecture 2

Question 1

Why is staining required?

Answer 1

In order to view the cell structure and the chemical nature of the tissues

Question 2

What is the standard staining procedure?

Answer 2

Lowest molecular weight stain applied first

then a larger counterstain is applied

Question 3

What is an example of a lower molecular weight stain?

Answer 3

Haematoxylin

Question 4

What is an example of larger weight stain?

Answer 4

Eosin

Question 5

What is progressive staining?

Answer 5

-Dye is applied and allowed to colour

Question 6

What is regressive staining?

Answer 6

Overstaining and then excess stain is removed

Question 7

What does haematoxylin do?

Answer 7

• Binds to basophilic substances

- Imparts a purple/black/blue colour to nculei

Question 8

What does eosin do?

Answer 8

Binds to acidophilic substances

-Imparts a red/pink colour to cytoplasm and inter cellular components

Question 9

What is the first step in the H&E stain with Harris’ Hematoxylin

Answer 9

-Rehydrated sections stained with Hematoxylin solution for 20-40 minutes