Question 1

The following are the preferred fixatives to be used on lipids except:
A)Frozen sections
B)Glutaraldehyde
C)Neutral buffered formalin
D)Osmium tetroxide

Accepted Answer

Neutral buffered formalin
Neutral buffered formalin is a fixative to avoid when fixing lipids. All the other three are the fixatives of choice for lipids.

Question 2

Which of the following statements is true about heat fixation?
A)It preserves overall morphology and preserves the internal structures
B)It does not preserve overall morphology, but it preserves internal structures
C)It does not preserve both overall morphology and the internal structures
D)It preserves overall morphology, but it does not preserve the internal structures

Accepted Answer

It preserves overall morphology, but it does not preserve the internal structures
It is a fact that heat fixation generally preserves overall morphology, but the disadvantage is that it does not preserve the internal structures of the specimen. All the other choices are false and incorrect.

Question 3

One disadvantage of using perfusion as a fixation process is:
A)It is a costly process
B)It makes the subject paralyzed
C)The volume of fixative used is smaller
D)The tissue does not die until it is fixed

Accepted Answer

It is a costly process
Perfusion is disadvantageous because for one, it covers a high cost, especially when a large volume of the fixative is used for larger organisms. It does not only paralyze the subject, but it eventually kills the subject as all the tissues become fixed and dies.

Question 4

Which statement best describes the rule of thumb for immersing a specimen in a fixative?
A)The volume of the fixative must be 5 times greater than the volume of the specimen
B)The volume of the fixative must be equal to the volume of the specimen
C)The volume of the fixative must be 20 times the volume of the specimen
D)The volume of the fixative should be slightly more than the volume of the specimen

Accepted Answer

The volume of the fixative should be 20 times greater than the volume of the specimen
In order for the fixative to effectively diffuse through the tissue to fix, the tissue sample must be immersed in a fixative of a volume that is 15 to 20 times greater than the total volume of the specimen. Other options above are inadequate and cannot effectively fix the sample through immersion.

Question 5

This process of fixation preserves structures in a state that is chemically and structurally as close to the living tissue as possible.
A)Heat fixation
B)Chemical fixation
C)Perfusion
D)Immersion

Accepted Answer

chemical fixation
In chemical fixation, a chemical fixative is used to stabilize the proteins, nucleic acids and muco-substances of the tissue by making them insoluble. Thus, chemical fixation preserves the structures both in its chemical and structural aspect as close to the living tissue as possible. Other options do not define chemical fixation.

Question 6

Which of the following fixatives do not belong to the group of oxidizing agents?
A)Potassium dichromate
B)Mercuric chloride
C)Chromic acid
D)Osmium tetroxide

Accepted Answer

Mercuric chloride
Mercuric chloride does not belong to the group of oxidizing agents since it is an example of a mercurial type of chemical fixative. All the other three choices are oxidizing agents.

Question 7

What are the advantages of utilizing frozen sections?
A)Lack of morphological detail
B)Much faster than other forms of fixation
C)Not exposed to organic solvents
D)Both B and C

Accepted Answer

both B and C
The advantages of using frozen sections is that it is much faster than other forms of fixation, you are not exposed to organic solvents, there is minimal exposure to fixatives, and it gives better preservation of antigenicity. It is disadvantageous since it lack morphological detail and it presents a potential biohazard. Therefore choice A is a disadvantage and choices B and C are advantages of frozen sections.

Question 8

The following are the factors that would affect the process of fixation, except:
A)Volume of the fixative used
B)Size of the specimen
C)Pressure on the specimen
D)Temperature

Accepted Answer

Pressure on the specimen
The pressure exerted on the specimen is not a factor that would affect the fixation process. All the other choices are the factors that can affect the process of fixation. Other factors include pH, osmolarity, duration, and time from removal to fixation.

Question 9

Which among the following statements is not true about penetration?
A)The rate of penetration is always affected by heat.
B)The penetration of fixatives can be improved by opening up a tissue sample.
C)The concentration of the fixative always affects penetration.
D)The presence of intestinal contents can inhibit the penetration of fixatives.

Accepted Answer

The concentration of the fixative always affects penetration.
The statement that is not true about penetration is that the concentration of the fixative always affects penetration. Although the concentration can possibly affect fixation, often times it does not affect the process. All the other statements are true about penetration.

Question 10

Which among the following is a physical method of fixation?
A)Microwave fixation
B)Cryo-preservation
C)Immersion fixation
D)Both A and B

Accepted Answer

Both A and B
The physical methods of fixation are heat fixation, microwave fixation, and cryo-preservation. Chemical methods of fixation are immersion fixation and perfusion fixation. Therefore, both choices of A and B are correct.

Question 11

Why is glutaraldehyde the preferred fixative for specimens in electron microscopy?
A)Glutaraldehyde is much easier to obtain than formaldehyde.
B)It excels at preserving the detailed structures of the cells and tissues
C)Tissues fixed with glutaraldehyde stain well with dyes.
D)Glutaraldehyde does not change the solubility of the fixed tissue.

Accepted Answer

It excels at preserving the detailed structures of the cells and tissues
The reason why glutaraldehyde is the preferred fixative for use in specimens in electron microscopy is that is very good at forming crosslinks between molecules. With this ability, glutaraldehyde is able to preserve the detailed structures of cells and fixed tissues excellently. All the other statements are inaccurate and do not explain why it is the choice for electron microscopy specimens.

Question 12

Among the statements about antigen preservation, which among the following is not correct?
A)All reactions with formaldehyde-fixed specimens can be reversed.
B)The quality of antigen preservation varies with respect to the type of fixative used.
C)The ability to preserve antigens is important when choosing a fixative to use.
D)Some fixation reactions are reversible in aldehyde-fixed specimens.

Accepted Answer

All reactions with formaldehyde-fixed specimens can be reversed.
Preservation and retrieval of certain antigens are important in immunohistochemistry. It has been discovered that there are some reversible reactions with respect to formaldehyde-fixed specimens, but not all of them are reversible. Thus, choice A is not accurate. All the other choices are true about antigen preservation.

Question 13

Which of the following statements is true about temperature being a factor in fixation?
A)Fixation is usually done at room temperature
B)As temperature increases, the speed of fixation decreases
C)"Cooking" the specimen is accepted in fixation.
D)As the temperature increases, the fixation speed remains the same.

Accepted Answer

fixation is usually done at room temperature
It is a common practice to conduct fixation at room temperature. Although as temperature increases, the rate of fixation also increases, great care is observed not to "cook" the specimen during fixation. All the other choices describing temperature are incorrect.

Question 14

What is the suitable pH for fixation?
A)pH 2 to 3
B)pH 4 to 6
C)pH 6 to 8
D)pH 7 to 9

Accepted Answer

pH 6 and 8
The suitable pH for fixation to happen is from pH 6 to pH 8. Outside this range, alterations may arise that are destructive to the structural preservation of tissue.

Question 15

What type of fixative gives the best result in fixation?
A)Slightly hypertonic fixative
B)Hypertonic fixative
C)Hypotonic fixative
D)Isotonic fixative

Accepted Answer

Slightly hypertonic fixative
The type of fixative that gives the best result in fixation is the slightly hypertonic fixative. This is for the reason that the osmolality of a slightly hypertonic fixative is between 400-450mOsm, which gives the best result in fixation. Hypertonic fixatives causes shrinkage of the cell, while isotonic and hypotonic fixatives give rise to the swelling of the cell and the fixation quality becomes poor.

Question 16

What is the preferred duration of fixation when using buffered formalin?
A)1 to 2 hours
B)2 to 6 hours
C)48 hours
D)72 hours

Accepted Answer

2 to 6 hours
The preferred duration of fixation when using buffered formalin is 2 to 6 hours. A period of 1 to 2 hours causes poor fixation, while 48 to 72 hours of fixation using buffered formalin may cause shrinkage and firmness of the tissue sample. That is why 2 to 6 hours is the preferred fixation time when using buffered formalin for it will not cause any distortion or alteration of the tissue sample.

Question 17

As a histotechnician, one must know the basics of fixation before it occurs. One of the basic principles to remember is the ideal size of the tissue. Therefore, what is the ideal size of the tissue before fixing it? A)0)5 cm² B)1 cm² C)2 cm² D)3 cm²

Accepted Answer

2cm² As a histotechnician one must know the basics of fixation before conducting it. One of these is the ideal size of the tissue for fixation, which is 2 cm². This is the ideal and preferred size of the tissue for the reason that with this size, it can maintain a sufficient fixation of the tissue. Other options are not ideal sizes to attain quality fixation.

Question 18

Aside from considering the adequate size of the tissue sample, the histotechnician must also take note of the sample's thickness. Which among the following is the ideal thickness of the tissue sample to attain quality fixation?
A)1 mm
B)2 mm
C)3 mm
D)4 mm

Accepted Answer

4 mm
The ideal thickness of the tissue sample is at 4 mm in order to attain quality fixation. One must also remember that thickness is another property of a tissue that is inseparable to its size when aiming for an adequate fixation of the tissue samples. Other thickness options would not result in quality fixation.

Question 19

Which of the following tissue samples is fixed first before sectioning or grossing?
A)Heart
B)Brain
C)Liver
D)Pancreas

Accepted Answer

Brain
The tissue sample that is fixed first before grossing or sectioning is the brain. This is for the reason that the brain tissue is very supple when not fixed and is very difficult to gross and section. Other organs in the choices do not undergo such process first.

Question 20

If a histotechnician receives a sample that contains glycogen, what fixative of choice is suitable for the demonstration and preservation of glycogen?
A)Neutral buffered formol saline
B)Rossman's fluid
C)Carnoy's fluid
D)Heidenhain's fluid

Accepted Answer

Rossman's fluid
If a histotechnician receives a sample that contains glycogen, the fixative of choice that is suitable for the demonstration and preservation of glycogen is Rossman's fluid. This is because Rossman's fluid preserves glycogen better and due to this, it demonstrates more glycogen.

Quiz 1: Fixation

The following are the preferred fixatives to be used on lipids except:

Which of the following statements is true about heat fixation?

One disadvantage of using perfusion as a fixation process is:

Which statement best describes the rule of thumb for immersing a specimen in a fixative?

This process of fixation preserves structures in a state that is chemically and structurally as close to the living tissue as possible.

Which of the following fixatives do not belong to the group of oxidizing agents?

What are the advantages of utilizing frozen sections?

The following are the factors that would affect the process of fixation, except:

Which among the following statements is not true about penetration?

Which among the following is a physical method of fixation?

Why is glutaraldehyde the preferred fixative for specimens in electron microscopy?

Among the statements about antigen preservation, which among the following is not correct?

Which of the following statements is true about temperature being a factor in fixation?

What is the suitable pH for fixation?

What type of fixative gives the best result in fixation?

What is the preferred duration of fixation when using buffered formalin?

As a histotechnician, one must know the basics of fixation before it occurs. One of the basic principles to remember is the ideal size of the tissue. Therefore, what is the ideal size of the tissue before fixing it?

Aside from considering the adequate size of the tissue sample, the histotechnician must also take note of the sample's thickness. Which among the following is the ideal thickness of the tissue sample to attain quality fixation?

Which of the following tissue samples is fixed first before sectioning or grossing?

If a histotechnician receives a sample that contains glycogen, what fixative of choice is suitable for the demonstration and preservation of glycogen?