Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

HPCT MIDTERMS > WAX IMPREGNATION AND EMBEDDING > Flashcards

WAX IMPREGNATION AND EMBEDDING Flashcards

1
Q

What are the type of tissue imprgnating medium?

A
  1. Paraffin wax
  2. Celloidin (Collodion)
  3. Gelatin and plastic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

It is the simplest, most common and best embedding medium. VERY RAPID

A

Paraffin Wax Impregnation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the melting point of paraffin wax?

A

56C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If the lab temp is between 20-24, what is the melting point of paraffin wax?

A

54-58C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If the lab temp is between 15-18, what is the melting point of paraffin wax?

A

50-54C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the advantages of Paraffin wax?

A
  1. Thin sections may be cut without undue distortion
  2. Rapid, and can be prepared within 24 hours
  3. Tissue blocks may be stored in paraffin for an INDEFINITE period of time after impregnation
  4. Permits staining
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the disadvantages of paraffin wax?

A
  1. Overheated paraffin can make specimen brittle
  2. Prolonged impregnation will cause excessive shrinkage and hardeing
  3. Inadequate impregnation will cause retention of the clearing agent
  4. Paraffin processing is not recommended for fatty tissues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are 3 ways paraffin wax may be performed?

A
  1. Manual processing
  2. Automatic processing
  3. Vacuum embedding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

This method makes use of automatic tissue processing machine or autotechnicon

A

Automatic processing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many changes of wax are required to remove the clearing agent for automatic processing?

A

2-3 changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many parts are there for automatic processing?

A

12 individual processing steps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

This involves the wax impregnation under negative atmospheric pressure inside an embedding oven

A

Vacuum embedding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

It provides more rapid wax penetration of tissue

A

Vacuum embedding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the reduced percentage of the time required for complete impregnation from the normal time required for tissue processing?

A

25-75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the precautions in wax impregnation?

A
  1. Tissues should not be left in paraffin wax for longer period of time than is necessary
  2. Over heated paraffin wax will also produce shrinkage and harden tissue and destroy lymphoid tissues completely
  3. Paraffin wax must be from free dust water droplets and other foreign matters
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Give the 6 substitutes for Paraffin wax

A
  1. Paraplast
  2. Embeddol
  3. Bioloid
  4. Tissue mat
  5. Ester wax
  6. Carbowax
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

This paraffin wax substitute is used for large dense tissue blocks such as bones and brain

A

Paraplast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the MP of the ff Paraffin wax substitutes?
1. Paraplast
2. Embeddol
3. Ester wax

A
  1. Paraplast: 56-57C
  2. Embeddol: 56-58C
  3. Ester wax: 46-48C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A paraffin wax substitute that is a mixture of highly purified paraffin and synthetic plastic polymers

A

Paraplast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

This paraffin wax substitutes is for less brittle and less compressible than paraplast

A

Embeddol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

This paraffin wax substitute is a synthetic wax, recommended for embedding eyes

A

Bioloid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

This paraffin wax substitute is a product of paraffin, containing rubber, with same property as paraplast.

A

Tissue mat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

This paraffin wax substitute is harder than paraffin.

A

Ester wax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Ester wax is soluble in _________ and ther clearing agents

25
This paraffin wax substitute is **not soluble in water**. Sliding and basic sledge microtome is recommended for processing this wax.
Ester wax
26
This paraffin wax substitute is soluble and miscible with water.
Carbowax
27
tissues are fixed, washed out and transferred directly in this paraffin wax substitute
Carbowax
28
True or False: Carbowax does not require dehydration and clearing due to its solubility and miscibility to water
True
29
This paraffin wax substitute is suitable for **many enzyme histochemical studies**
Carbowax
30
What is **celloidin** also known for?
Collodion
31
This impregnating medium is very slow (could take days to weeks) to solidify and is prone to contaminants
Celloidin (Collodion)
32
What are the 3 types of celloidin?
1. Wet celloidin 2. Dry celloidin 3. Nitrocellulose method (Low Viscosity Nitrocellulose)
33
This type of celloidin is for bones, teeth, large brain sections and whole organs
Wet celloidin
34
This type of celloidin is for processing whole eye sections, stored in Gilson's mixture
Dry celloidin
35
What are the components of Gilson's mixture?
Cedarwood oil + chloroform = transparency
36
It is just another form of celloidin
Nitrocellulose Method (Low Viscosity Nitrocellulose
37
This impregnating medium is rarely used and water soluble
Gelatin
38
How to prevent **molds in gelatin**?
Add 1% phenol!
39
**Plastic and resin** is classifies into 3 parts, what are those?
1. Epoxy 2. Polyester 3. Arylic
40
This process is done after wax impregnation
Embedding/casting/blocking
41
This process involves placing the tissue in a mold containing the medium
Embedding/casting/blocking
42
This is a process by which the tissue is arraged in a precise positions in the mold
Embedding/casting/blocking
43
Enumerate steps in embedding/casting/blocking
1. Remove tissue from cassette 2. Fill mould with wax and orientate tissue 3. Cool and flatten as required 4. Add cassette, fill with wax and put on cold plate 5. Remove cassette from mould 6. Block is now ready for sectioning (microtomy)
44
Consists of two L-shaped strips of heavy brass or metal arranged on a flat metal plate, can be adjusted
Leuckhart's embedding mold
45
Made up of a **series** of interlocking plates resisting on a flat metal base with several **compartments**
Compound Embedding Unit
46
A special stainless steel base mold fitten with a plastic embedding ring serves as block holder
Plastic embedding rings and base mold
47
It is an example of plastic mold equipped with warm to manage impregnated specimen, and a cold plate at -5C for rapid solidification.
Tissue tek
48
available in 3 different size and simply peeled off once at a time as soon as the wax solidified
Peel away
49
Also used in ordinary refrigerators, tissue block may be removed by bending the plastic tray
Plastic Ice Tray
50
Have advantage of cheap and easy to make, have accurate identification. Utilized for embedding celloidin blocks but equally useful for paraffin wax blocks
Paper boats
51
Tissues are first embedded with a supporting medium such as agar or nitrocellulose, then embedded with paraffin wax for second time.
Double embedding
52
This embedding method reduces antigenicty, toxic and damage tissues
Epoxy
53
What are the types of epoxy?
1. Bisphenol 2. Glycerol 3. Cyclohexene dioxide
54
Bisphenol A other name?
Araldite
55
Glycerol other name?
epon
56
Cyclohexene dioxide other name?
Spurr
57
Other type of cyclohexene dioxide?
Maraglass 665
58
It is another embedding method that is not often used
Polyester
59
Another embedding methods that is used extensively for light microscopy
Acrylic

HPCT MIDTERMS (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions