Lecture 2: Intro to Histology

Question 1

What is the maximum resolving power of an EM?

Answer 1

0.2 nm

Question 2

What are the 4 tissue types?

Answer 2

Connective Tissue, Epithelia, Muscle, Nerve

Question 3

Explain fixation, its process and some benefits.

Answer 3

Process by which we toughen tissues using formalin or formaldehyde. It works by chemically crosslinking molecules. It can act as an antimicrobial agent.

Question 4

When is paraffin embedding used?

Answer 4

Used on fixed tissues after we dehydrate them (with alcohol). Allows for sectioning

Question 5

Briefly explain haemotoxylin.

Answer 5

Stains blue/purple and binds to anionic or negative components. Binds especially to nucleus because of the negative phosphate groups. Substances that bind to it are commonly known as basophilic.

Question 6

Briefly explain eosin.

Answer 6

Stains pink/orange, binds to cationic or positive components. Binds especially to amino acids or proteins,