Mucous Membranes

Question 1

The mouth is lined by a moist ___ membrane.

Answer 1

mucous

Question 2

The mucous membrane is an organ composed of what 2 tissues?

Answer 2

epithelium and connective tissue

Question 3

Which tissue does not contain blood vessels or salivary glands?

Answer 3

epithelium

Question 4

Connective tissues consist of a ___ ___ and sometimes a submucosa. Both layers contain ___ ___ but minor ___ glands are mostly found in the submucosa.

Answer 4

lamina propria; blood vessels; salivary

Question 5

___ from both major and minor salivary glands travel thru connective tissue to communicate with the mucosal surface.

Answer 5

Ducts

Question 6

What other tissue is found embedded in the oral mucosa?

Answer 6

lymphoid tissue

-lingual and palatine tonsils

Question 7

Which layer of the mucous membrane is the better barrier for protections, epithelium or basal lamina?

Answer 7

epithelium

Question 8

What two cells are involved in the anti-microbial protection of the mucous membrane?

Answer 8

immune cells and epithelial cells

Question 9

In addition to the tonsils, which cell type is found mainly in the lamina propria?

Answer 9

immune cells

Question 10

Epithelial cells synthesize and secrete several antimicrobial molecules. Name one important example.

Answer 10

beta-defensins

Question 11

When the mucous membrane is invaded by pathogenic bacteria, different varieties of ___-___ are secreted in different layers of the epithelium.

Answer 11

beta-defensins

Question 12

Beta-defensins are ___-rich and cationic. They bind to ___ charges on bacterial membranes and cause them to ___.

Answer 12

cysteine; negative; permeabilize

Question 13

Another function of the mucous membrane is ingestion due to what properties?

Answer 13

its flexibility and moist surface

Question 14

T/F. The oral mucosa is not highly innervated.

Answer 14

False, the oral mucosa IS highly innervated and this augments protective and ingestive functions

Question 15

Which tissue is capable of more types of sensations, dentin/pulp, PDL or oral mucosa?

Answer 15

oral mucosa

Question 16

What fibers are associated with pain in the dentin and pulp?

Answer 16

C, A-delta, A-beta

Question 17

What are the two sensations found in the PDL?

Answer 17

C and A-delta = pain

A-beta = proprioceptive

Question 18

Match the fibers of the oral mucosa with their sensations.

A. A-beta
B. A-delta
C. C

1. touch
2. pain
3. thermal
4. taste

Answer 18

A - 1
B - 2, 3, 4
C - 2, 3

Question 19

What type of epithelium is found in all types of oral epithelium?

Answer 19

stratified squamous epithelium

Question 20

The epithelium has an ability to self-___. The deep layers are involved in ___ ___. The superficial layers migrate and once matured they are ___ off.

Answer 20

renewal; cell division; sloughed

Question 21

T/F. Relatively fast turnover can speed healing, but also can make tissues more vulnerable to conditions that affect cell division (chemotherapy & radiotherapy).

Answer 21

True.

Question 22

Most of the volume of the epithelium is occupied by ___. Which cell is the most numerous?

Answer 22

cells; keratinocytes

Question 23

Give some examples of non-keratinocytes found in the epithelium.

Answer 23

Merkel cells - sensory - basal layer
Melanocytes - pigment cells - basal layer
Langerhan (dendritic) cells - immune - supra-basal layers

Question 24

Which non-keratinocytes are better known as clear cells?

Answer 24

Melanocytes and Langerhan (dendritic) cells

Question 25

How can you distinguish langerhan cells from melanocytes if they both appear clear upon H&E staining?

Answer 25

location

Question 26

What do clear cells lack when stained?

Answer 26

cytokeratin

Question 27

Special staining reveals that melanoctes have a cell body with processes located in which layer?

Answer 27

basal layer

Question 28

Langerhan cells are similar in structure to melanocytes but where are they found?

Answer 28

suprabasal layer

Question 29

T/F. Keratinized and non-keratinized epithelium have the same clinical appearance.

Answer 29

False, they have distinctive clinical appearances.

Question 30

Microscopic characteristics of both keratinized and non-keratinized epithelium contain a ___ layer and ___ cell layer.

Answer 30

basal; prickle (stratum spinosum)

Question 31

T/F. The superificial layers between keratinized and non-keratinized epithelium is distinct.

Answer 31

True.

Question 32

Keratinized epithelium contains no ___ , is ___ and has a tough appearance. Whereas, the ___ layer is otherwise flexible and contains organelles.

Answer 32

organelles; dehydrated; superficial

Question 33

All epithelial cells = ___ and contain ___.

Answer 33

keatinocytes; cytokeratins

Question 34

Cytokeratins assemble into ___ ___ to provide cytoskeletal support. What are the two types?

Answer 34

intermediate filaments; type I (acidic) and type II (basic)

Question 35

Mutations in cytokeratins cause what disease?

Answer 35

Epidermolysis bullosa simplex (EB simplex) It is rare, and has characteristic blistering in response to minor trauma. It is most severe in the epidermis but also has oral consequences.

Question 36

Different epithelial ___ and ___ contain characteristic cytokeratins.

Answer 36

layers; tissues

Question 37

T/F. Cytokeratin expression remains the same in normal and disease states. But, mutations in cytokeratin genes can produce regionally-specific diseases.

Answer 37

False, cytokeratin expression CAN change with disease state | True, mutations in cytokeratin genes produce regionally specific diseases.

Question 38

Different ___ types are important for ___ properties of keratinized vs non-keratinized epithelia. In both, the ___ of cytokeratin ___ in superficial layers.

Answer 38

cytokeratins; mechanical; amount; increases

Question 39

How do keratinized cytokeratins promote aggregation?

Answer 39

thru the formation on tonofibrils found in the prickle layer

Question 40

How do keratinized cytokeratins promote binding to another molecule?

Answer 40

with fillagrin, a main component of keratohyalin granules - found in the granular layer.

Question 41

Describe the superficial layer of keratinized epithelium.

Answer 41

very flat cells dehydrated no organelles packed with cytokeratin (tonofibril) / filligrin complexes

Question 42

T/F. In non-keratinized epithelium, cytokeratin does not promote aggregation and cannot complex with fillagrin but the superficial layers are flat, dehydrated and retain nuclei and cytokeratin tonofilaments.

Answer 42

False, In non-keratinized epithelium, cytokeratin does not promote aggregation and cannot complex with fillagrin but the superficial layers are NOT flat OR dehydrated and retain nuclei and cytokeratin tonofilaments.

Question 43

T/F. Non-keratinized epithelium is tougher but less flexible than keratinized epithelium.

Answer 43

False, KERATINIZED epithelium is tougher but less flexible than NON-keratinized epithelium.

Question 44

What are membrane bound organelles filled with?

Answer 44

glycolipids

Question 45

Membrane coating ___ first appear in the upper ___ cell layers and are released in more ___ layers to coat cells. This occurs in both epithelium and serves as an ___ barrier to aqueous substances.

Answer 45

granules; prickle; superficial; INTERcellular

Question 46

Differences in chemical composition creates ___ (> /

Answer 46

>

Question 47

A ___ envelope is a 15nm cross-linked protein sheath comprised of ___ and other proteins.

Answer 47

cornified; loricrin

Question 48

Most of the volume of the lamina propria is occupied by ___ that contains type ___ and type ___ collagen and ___.

Answer 48

ECM; type I; type III; elastin

Question 49

T/F. The relative amount of type I : type III collagen is greater for less flexible regions of the oral cavity.

Answer 49

True.

Question 50

___ is more prominent in the oral mucosa than in pulp or PDL.

Answer 50

elastin

Question 51

Connective tissue ___ are scalloped with ___ ___ between the convoluted ____ layer of the epithelium and ___ layer of the lamina propria.

Answer 51

papillae; rete pegs; papillary; reticular

Question 52

What separates the lamina propria from bone and muscle?

Answer 52

submucosa

Question 53

List some structures that do not have any submucosa.

Answer 53

lp-muscle, tongue, lp-bone (mucoperiosteum), gingiva, hard palate next to gingiva, rugae region, median raphe

Question 54

The lining mucosa has ___ epithelium and is found where?

Answer 54

non-keratinized; buccal and labial mucosa and floor of mouth

Question 55

What are the clinical implications of the lining mucosa?

Answer 55

incisions more likely to gap and need to be sutured. injections are less painful

Question 56

Which structures are thin and have keratinized epi, exterior skin, vermillion zone, or labial mucosa?

Answer 56

exterior skin and vermillion zone

Question 57

What type of glands are found in the following: exterior skin, vermillion zone, and labial mucosa?

Answer 57

exterior skin - sweat glands vermillion zone - no sweat or mucous glands labial mucosa - mucous glands

Question 58

Which mucosa has fewer collagen fibers and more elastic fibers, the masticatory or lining mucosa?

Answer 58

lining,mucosa has more collage fibers and fewer elastic fibers

Question 59

What are the clinical implications of the masticatory mucosa?

Answer 59

incisions don't gape, may not require suturing, injections are more painful

Question 60

The sulcular and junctional epithelium are part of the ___.

Answer 60

periodontium

Question 61

The sulcular epithelium is part of the ___ gingiva which faces the tooth and generally has ____ epithelium.

Answer 61

free; non-keratinized

Question 62

T/F. The junctional epithelium is highly permeable leading it susceptible to inflammation.

Answer 62

True.

Question 63

Which junctional epitelium has type IV and VII epithelium, external (JE/lamina propria) or internal (JE/tooth)?

Answer 63

internal

Question 64

Collagen components of the ___ ___ provide direct connection to collage of lamina propria.

Answer 64

basal lamina

Question 65

Consistent with it's origin from ___ ___ ___, JE expressed a protein initially associated with ameloblasts.

Answer 65

reduced enamel epithelium

Question 66

T/F. The "col" is also characterized by JE.

Answer 66

True.

Question 67

T/F. Despite its specialized nature, JE can regenerate relatively rapidly and around dental implants.

Answer 67

True.

Question 68

How does the vascular supply get to the gingiva?

Answer 68

superior alveolar / palatine AND inferior alveolar/buccal/mental/sublingual feed into the PDL, interdental septa and oral mucosa then to the gingiva