Histology Self-Study Cards

Front 1

List the 9 steps of the paraffin technique

Back 1

1- Obtaining of the tissue.
2- Fixation.
3- Dehydration.
4- Clearing.
5- Impregnation.
6- Embedding.
7- Sectioning.
8- Staining.
9- Mounting.

Front 2

What are the advantages of paraffin technique?

Back 2

1- It gives thin sections.
2- The sections are easily stained.
3- It gives serial sections.

Front 3

What are the disadvantages of the paraffin technique?

Back 3

1- The heat and chemicals may damage the tissue.
2- Fat is dissolved.
3- Most enzymes are inactivated.

Front 4

What is the difference in the size of the tissue sample between E/M & L/M

Back 4

L/M: Small pieces. 1cm3
E/M: Very small pieces: 1mm

Front 5

What do we use in fixation when we're preparing a tissue sample?

Back 5

L/M: Formol-saline
E/M: Glutaraldehyde 2.5% in 0.1M phosphate buffer and Osmium tetroxide 1% in the same buffer.

Front 6

What do we use in dehydrating the tissue sample.

Back 6

L/M: Ascending grades of Alcohol.
E/M: Ascending grades of Alcohol or Acetone.

Front 7

What do we use in clearing?

Back 7

L/M: Xylene or Benzene.
E/M: Propylene oxide.

Front 8

what do we use in impregnation & embedding?

Back 8

L/M: Paraffin or Paraplast
E/M: Hard media as epon and araldite.

Front 9

What do we use to section the embedded tissue sample?

Back 9

L/M: Microtome (5-8 micrometer)
E/M: ultramicrotome (50-100 nm)

Front 10

Name the microscopes that can be used to study living cells:

Back 10

1- Phase contrast.
2- Dark field microscopy.
3- Oblique illumination.
4- Bright field.

Front 11

What are the difference between L/M and E/M:

Back 11

L/M:
1- Light rays are used.
2- Mirrors and lenses are used.
3- It gives colored pictures.
4- It has a limited power of magnification.
E/M:
1- Electron beams are used.
2- Electromagnetic fields are used.
3- It gives black and white pictures.
4- It has a very high power of magnification.

Front 12

How does the Hematoxylin Eosin stain works?

Back 12

Hx stains the basophilic structures such as DNA & RNA blue.
Eosin stains Acidophilic structures red.

Front 13

Silver stain is used for:

Back 13

1- Retucular fibers.
2- Golgi apparatus.
3- Nerve cells and fibers.

Front 14

The silver stain gives the structures it stains what colors?

Back 14

Brown to black

Front 15

What is the PAS stain used for?

Back 15

It is used to stain carbohydrates and glycoproteins.

Front 16

PAS gives the structures it stains a ... color

Back 16

purple

Front 17

What can we stain with PAS?

Back 17

1- Mucus of goblet cells.
2- Brush border of absorbative cells.
3- Glycocalyx.
4- Basement membrane.

Front 18

Sudan III is used to stain .... and it gives them a(n) .... color

Back 18

Lipids, Orange color

Front 19

What can we use to stain lipids?

Back 19

1- Sudan III. (Orange)
2- Sudan black. (Black)
3- Osmium tetroxide. (Blue)

Front 20

Metachromasia is:

Back 20

Change in the color of the used stain as it combines chemically with the biological structures within the cells.

Front 21

Give an example of Metachromasy:

Back 21

1- Mast cells stained with toluidine blue, the cytoplasmic granules are stained reddish blue.

Front 22

Give an example of vital(in vivo) staining

Back 22

Macrophages stained with trypan blue or indian ink

Front 23

Give 2 examples of supravital staining

Back 23

1- Reticulocytes with Brilliant cresyl blue.
2- Mitochondria with Janus green B.

Front 24

Peroxidase is used for labelling

Back 24

antibodies

Front 25

The Interphase is

Back 25

The stage in the cell cycle at which the cell is not dividing.

Front 26

Functions of the nucleus are:

Back 26

1- Preservation of the genetic material.
2- Direction of the formation of certain proteins of the cell.

Front 27

What is the structure of the Interphase nucleus?

Back 27

1- Nuclear membrane.
2- Chromatin.
3- Nucleolus.
4- Nuclear sap.

Front 28

How does the nuclear membrane appear under the E/M and L/M?

Back 28

L/M: Single basophilic line.
E/M: 2 membranes each 8nm in thickness, separated by a 20nm perinuclear space.

Front 29

What are the fibrous lamina?

Back 29

A thin layer formed of filamentous material to which clumps of nuclear chromatin are attached.

Front 30

What is the diameter of the nuclear pores?

Back 30

40-100 nm

Front 31

What closes the nuclear pores?

Back 31

a thin pore diaphragm

Front 32

What's the diameter of the central channel of the complex of the nuclear pores?

Back 32

10 nm

Front 33

Describe how Chromatin appears under the E/M and the L/M:

Back 33

L/M: basophilic granules.
E/M: 2 types:
1- Condensed(heterochromatin, inactive).(constitutive and faculative)
2- Extended chromatin.

Front 34

What's a nucleosome?

Back 34

Looping and coiling of the DNA, it equals a central core of 2 histones and DNA which is coiled around that core by 2.5 turns

Front 35

How does the nucleolus appear under the L/M?

Back 35

1 or more rounded basophilic(RNA, nucleolus associated chromatin) bodies

Front 36

What's the size of the nucleolus?

Back 36

1 micrometer or more

Front 37

What does the nucleolus consist of?

Back 37

5% DNA, Little RNA, A lot of proteins

Front 38

How does the nucleus look like under the E/M?

Back 38

Dark material:
1- Pars fibrosa.(site of RNA synthesis)
2- Pars granulosa.(ribosomes)

Front 39

What's the diameter of pars granulosa?

Back 39

12-15 nm

Front 40

What's the diameter of the pars fibrosa?

Back 40

5 nm

Front 41

What does the less dense material in the nucleolus consist of?

Back 41

Chromosomal loops(10 nm)
Amorphous matrix made of proteins.

Front 42

Which cells have different number of nucleoli?

Back 42

1- Mononucleated cells. e.g. nerve cells
2- Binucleated cells, e.g, liver cells, Zona fasiculata of adrenal gland, top layer of tranditional epithelium.
3- Multinucleated cells, e.g, osteoclasts.

Front 43

The nucleus is basal in the

Back 43

columnar epithelium

Front 44

What is the type of the nucleus of the lymphocytes?

Back 44

Condensed

Front 45

What are the organoids?

Back 45

living contents of the cytoplasm which are essential for life,

Front 46

What are the membranous organelles?

Back 46

1- Cell membrane.
2- Mitochondria.
3- Endoplasmic reticulum.
4- Golgi apparatus.
5- Lysosomes.
6- Peroxisomes.

Front 47

What are the non-membranous organoids?

Back 47

1- Ribosomes.
2- Microtubules.
3- Centrioles.
4- Cilia & flagella.
5- Microfilaments.

Front 48

What are the cytoplasmic inclusions?

Back 48

1- Stored food.
2- Pigment.
3- Crystals.

Front 49

Why can we see the cell boundary under the L/M?

Back 49

1- Due to artifacts.
2- The obliquity of sections.
3- Condensation of the stain.

Front 50

What's the diameter of the cell membrane?

Back 50

8-10 nm

Front 51

Why are cholesterol molecules found on the inner half of the cell membrane?

Back 51

because they increase the stability and stiffness of the cell membrane

Front 52

How can we stain mitochondria?

Back 52

a- Iron HX.
2- Supravital, Janus Green B.

Front 53

What's the size of the mitochondria?

Back 53

0.1-0.5 micrometer in width
up to 10 micrometers in length

Front 54

What are the sizes of lysosomes?

Back 54

0.2-0.4 micrometer

Front 55

What is the diameter of peroxisomes?

Back 55

0.3-1.5 micrometer

Front 56

What does the cilia consist of?

Back 56

1- Basal Body. Kinetosome.
2- The shaft. Axoneme.
3- Rootlets.