Impregnation, Embedding, Microtomy

Question 1

What is impregnation in histology?

Answer 1

Infiltration process

Question 2

What is the main purpose of tissue impregnation?

Answer 2

Firm consistency for cutting

Question 3

What happens to tissue without firm consistency?

Answer 3

Collapses during cutting

Question 4

What is the ideal volume of embedding medium?

Answer 4

At least 25x tissue volume

Question 5

What is the melting point of paraffin wax?

Answer 5

54-58 ℃

Question 6

What are the three methods of impregnation in histology?

Answer 6

Paraffin, Celloidin, Gelatin

Question 7

Which impregnation method is most common?

Answer 7

Paraffin wax impregnation

Question 8

Which impregnation process is the most expensive?

Answer 8

Gelatin impregnation

Question 9

Manual Processing requires?

Answer 9

4 changes of wax

Question 10

Total time for Manual Processing?

Answer 10

1 hour

Question 11

What does Automatic Processing use?

Answer 11

automatic tissue processing machine

Question 12

Benefit of Automatic Processing?

Answer 12

less time and labor

Question 13

What is Vacuum Embedding?

Answer 13

impregnation under negative pressure

Question 14

Recommended for urgent biopsies?

Answer 14

Vacuum Embedding

Question 15

Reduces impregnation time by?

Answer 15

25-75%

Question 16

Effect of overheating paraffin?

Answer 16

shrinkage and hardening

Question 17

What temperature must the paraffin oven be maintained at?

Answer 17

2-5℃ above melting point

Question 18

What is Celloidin?

Answer 18

Purified nitrocellulose

Question 19

When is Celloidin suitable?

Answer 19

Large cavities, hard tissues

Question 20

What is a con of Celloidin?

Answer 20

slow and tedious

Question 21

What is the recommended use for Wet Celloidin Method?

Answer 21

bones, teeth, organs

Question 22

What does Dry Celloidin Method use?

Answer 22

Gilson’s mixture

Question 23

Ideal application for Gelatin Impregnation?

Answer 23

fragile specimens

Question 24

What is the tissue thickness limit for Gelatin embedded specimens?

Answer 24

2-3 mm

Question 25

What solution prevents mold growth in Gelatin?

Answer 25

1% PHENOL SOLUTION

Question 26

What is the process called for arranging tissue in a mold?

Answer 26

Orientation

Question 27

What temperature is paraffin melted for embedding?

Answer 27

5-10℃ above melting point

Question 28

Sizes of Peel-aways

Answer 28

3 different sizes

Question 29

Use of Plastic Ice Trays

Answer 29

busy routine laboratories

Question 30

Use of Paper Boat

Answer 30

embedding celloidin and paraffin blocks

Question 31

Celloidin/Nitrocellulose Method

Answer 31

hard tissues, bones, teeth

Question 32

Low Viscosity Nitrocellulose (LVN)

Answer 32

soluble in ether and alcohol

Question 33

Double Embedding Method

Answer 33

celloidin and paraffin

Question 34

Which microtome is favored for very hard tissue?

Answer 34

Base-Sledge Microtome

Question 35

What type of microtome is most dangerous?

Answer 35

Base-Sledge Microtome

Question 36

Describe the Standard Sliding Microtome.

Answer 36

Knife moves; block stationary

Question 37

Which microtome is used for paraffin embedded sections?

Answer 37

Rotary Microtome

Question 38

Most popular microtome for routine studies?

Answer 38

Rotary Microtome

Question 39

Simplest microtome for serial sections?

Answer 39

Rocking Microtome

Question 40

Which microtome is used for unembedded frozen sections?

Answer 40

Freezing Microtome

Question 41

What replaced the Freezing Microtome in most labs?

Answer 41

Cryostat

Question 42

For what work is the Ultrathin Microtome used?

Answer 42

Electron microscopy

Question 43

What is Honing?

Answer 43

Removal of nicks and irregularities on a knife edge

Question 44

What is stropping?

Answer 44

Process to polish knife

Question 45

What is the direction for stropping?

Answer 45

Toe to Heel

Question 46

What is the purpose of stropping?

Answer 46

Polish and sharpen knife