Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Histopathology > Impregnation and Embedding > Flashcards

Impregnation and Embedding Flashcards

1
Q

Process whereby the clearing agent is completely removed from the tissue and replaced by a medium that will completely fill all the tissue cavities.

A

Impregnation (infiltration)

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

Enumerate 4 types of embedding and impregnation media.

A
  1. Paraffin Wax
  2. Celloidin
  3. Gelatin
  4. Plastic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the most common, simplest, and best embedding medium used for routine tissue processing?

A

Paraffin wax

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

What embedding medium allows cut sections to stick together edge-to-edge, forming a “ribbon” of sections, but is not recommended for fatty tissues?

simplest, most common, and best embedding wax

A

Paraffin wax

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

True or False.

An overheated specimen makes the specimen to be brittle.

A

True

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

What is the melting point of paraffin wax?

A

56°C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the melting point of a paraplast?

A

56°-57°C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Identify the type of wax.

  • More elastic/resilient
  • Permits large dense tissue blocks (bones & brain) to be cut easily
  • Better ribboning of sections
A

Paraplast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Identify the type of paraplast wax.

  • Synthetic wax substitute similar to Paraplast
  • Less brittle and compressible than Paraplast.
A

Embeddol

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

Identify the type of wax.

  • Harder than paraffin wax
  • H2O insoluble
  • Can be used for impregnation without prior clearing of tissue.
A

Ester wax

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

What is the melting point of ester wax?

A

46°-48°C

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

What is the other name for water-soluble waxes?

A

polyethylene glycol

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

What is the melting point of polyethylene glycol?

A

38°-42°C

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

What refers to the primary processor that is used today whereby tissue is stationary and fluids are pumped in and out of the pressurized chamber holding the tissue?

A

Closed system

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

What is the major advantage of using a closed system for tissue processors?

A

specimens cannot dry out in the tissue chamber in the event of malfunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is added to plastic polymer paraffin waxes that reduces infiltration time?

A

Dimethyl sulphoxide (DMSO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A purified form of nitrocellulose soluble in many solvents

A

Celloidin

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

Identify the media.

  • Permits cutting of thicker tissue sections
  • Crumbling of tissues avoided (flexible to use)
  • Suitable for specimens with large cavities
  • For hard and dense tissues
  • For large tissue sections of the whole embryo
  • Also recommended for processing of neurological tissues
A

Celloidin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Identify the media.

  • Rarely used except when dehydration is to be avoided and when tissues are subjected to histochemical and enzyme studies
  • Used as an embedding medium for delicate specimens and frozen section specimen
  • Does not require dehydration & clearing
20
Q

Identify the method of celloidin impregnation.

  • for bones, teeth, large brain sections, and whole organ
A

Wet celloidin method

21
Q

Identify the method of celloidin impregnation.

  • for processing the whole eye section
A

Dry celloidin method

22
Q

What paraffin wax method is the fastest and has negative atmospheric pressure that facilitates the complete removal of transition solvents?

23
Q

How many changes of wax are done on the manual paraffin wax method?

24
Q

What is the time interval between changes of wax during the manual paraffin wax method?

A

15 mins. interval

25
True or False. Tissues during gelatin impregnation should not be > 2-3 mm thick since gelatin-embedded specimens are harder to freeze than non-impregnated tissues.
True
26
- Also known as Blocking or Casting. - Process by which the impregnated tissue is placed into a precisely arranged positioning of a mold containing a medium which is then allowed to solidify.
Embedding
27
What refers to the formation of tissue block?
blocking
28
What refers to the process of placing the tissue in a molder?
Molding
29
It is the process by which tissue is arranged in a precise position in the mold during embedding, on the microtome, before cutting, and on the slide before staining.
Orientation
30
What temperature are paraffin-embedded tissues cooled?
-5℃
31
Identify the type of embedding. - 2% Celloidin for 3 days and subsequent paraffin - For large blocks of dense firm tissues (brain) - Obsolete
Double embedding
32
How much celloidin is used on double embedding?
2%
33
Identify the type of embedding. - Require dehydration through a graded series of ethyl alcohol, and unless miscible with ethanol - Requires the use of a transitional fluid (i.e. clearing agent) such as propylene oxide
Epoxy resin
34
What are the most commonly used epoxy resins?
Araldite, Epon and Spurr
35
At what temperature does hard blocks are polymerized?
60℃
36
What type of knife is used to cut 60-90 nm thick specimens?
Diamond knife
37
What type of knife is used to cut 0.5µm thick specimens?
Glass knife
38
Identify the type of embedding. - Originally introduced for **electron microscopy** in the mid-1950s - Superseded by more superior epoxides - Now seldom used
Polyester plastics
39
Identify the type of embedding. - Made up of esters of acrylic or methacrylic acid - used extensively for **light microscopy**
Acrylic plastics
40
What type of acrylic plastic is extremely hydrophilic, allowing many staining methods to be applied, yet tough enough when dehydrated to section well on most microtomes?
Polyglycol methacrylate (GMA
41
What type of acrylic plastic is widely used because of its hardness as the ideal embedding medium for undecalcified bone, for bone histomorphometry, and bone marrow hematopathology?
Methyl methacrylate (MMA)
42
What tissue blocks do not require chilling or refrigeration?
Celloidin blocks
43
Identify the blocking-out molds. - consists of two **L-shaped** strips of heavy brass or metal - recommended for routine use - too slow and cumbersome for use in a busy laboratory
Leuckhart's embedding mold
44
Identify the blocking-out molds. - made up of a series of **interlocking plates** resting on a flat metal base, forming several compartments. - has the advantage of embedding more specimens at a time, thereby reducing the time needed for blocking.
Compound embedding unit
45
Identify the blocking-out molds. - consist of a special stainless steel base mold fitted with a plastic embedding **ring**, which later serves as the block holder during cutting - one of its models is called the **Tissue Tek**
Plastic Embedding Rings And Base Mold

Histopathology (12 decks)

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