Histology Lecture 3a -- Oral Mucosas Flashcards

1
Q

Describe the epithelium of the skin on the face

A

Stratified squamous epithelium, keratinized and shows hair follicles, sebaceous glands, and sweat glands

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

Layer beneath the epithelium of the skin

A

Connective tissue layer called the dermis

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

2 layers of the dermis of the skin

A

Papillary layer

Reticular layer

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

Describe the organization of the papillary layer

A

Interdigitated with the rete pegs of the epithelium

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

Layer contained in the skin epidermis

A

Stratum granulosum layer with basophilic keratohyalin granules

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

Define stratum corneum of the skin

A

Dead cell layer that is orthokeratinized

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

Define orthokeratinized

A

The usual or true form of keratinization

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

Define the red border of lip

A

A transitional region from dry to wet surface epithelium (dry skin-type epithelium becomes the wet oral mucous membrane or oral mucosa)

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

What layer is the lamina propria of the oral mucosa continous with at the level of the lips

A

The dermis of the skin

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

Describe the keratinization of the lips

A

Epithelium is partially keratinized, so keratinized near the skin, but non-keratinizaed near the oral mucosa

The keratinized layer is thin, making the epithelium translucent

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

Describe the dermis/lamina propria of the lips

A

Rete pegs are very deep and the vessel-containing papillae of the lamina propria extend very close to the lip surface

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

Describe the anatomical location of the oral mucosa

A

Entire inside of the mouth except for the gingiva and the dorsal surface of the tongue

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

Describe the epithelium of the oral mucosa

A

Stratified squamous epithelium, nonkeratinized

Surface cells of the epithelium are squamou but contain nuclei and desquamate as living cells into the oral cavity

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

Describe the lamina propria of the oral mucosa

A

Very vascular (reason for deep red color of mucosa)

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

Layer beneath the lamina propria of the oral mucosa and its contents

A

Submucosa, which has small glands that constitute the minor salivary glands (may be serous, mucous or mixed)

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

Define the anatomical location of gingiva

A

gums surrounding the teeth and cover the entire hard palate

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

Define the mucogingival junction

A

Where the oral mucosa nad gingiva meet at a visible line in the mouth

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

Describe the epithelium of the gingiva

A

Modification of the stratified squamous epithelium. Has a stratum germanitavum and a stratum spinosum layer, but no stratum granulosum. Spinosum cells flatten and become keratinized, but do not die. They retain their nuclei until they desquamate.

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

Define parakeratinization

A

Type of keratinization found in the gingiva wherein the spinosum cells of the epithelium flatten and become keratinized, but do not die. Instead, they retain their nuclei (thin, flattened and not obvious) until they desquamate. Form a thick regular layer that stains deeply eosinophilic

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

What layer is the submucosa of the gingiva and hard palate continuous with?

A

Periosteum lining the alveolar bone or the palatine process of the maxilla (therefore the gingiva does not move freely over the bone)

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

Define the junctional epithelium of the gingiva

A

Gingiva reflects onto the tooth surface and the cells become modified for attachment to the tooth surface

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

What does the formation of the junctional epithelium of the gingiva involve?

A

Formation of hemidesmosomal attachments to the calcified surface of the tooth (can be to either the enamel or the cementum)

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

What is the only seal separating the “dirty (bacteria, etc)” oral cavity from the “inside” lamina propria and blood vessels supplying the gingiva?

A

Hemidesmosomal attachments

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

2 subdivisions of the palate

A

Hard palate

Soft palate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What underlies the mucosa of the hard palate?

A

Bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What underlies the mucosa of the soft palate?

A

Skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Describe the mucosa of the palate

A

Masticatory mucosa similar to that of the gingival (i.e. with a stratified squamous parakeratinized epithlium). Reflects around the soft elastic palate and the uvula where it is a stratified squamous nonkeratinizing epithelium, to become respiratory epithelium (pseudostratified ciliated columnar) on the nasal side of the palate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is the mucosa attached to the palatine bone in the hard palate region?

A

By a mucoperiosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Where can salivary glands be found in the palate?

A

Laterally in the mucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Differentiate between the two portions of the tongue

A
  • Free portion = covered entirely by epithelium
  • Attached portion = epithelial lining continues with the oral mucosa covering the floor of the mouth
31
Q

Describe the musculature of the tongue

A

Striated muscle with fibres that run in all directions and are:

  • Intrinsic = origin and insertion from the connective tissue within the tongue
  • Extrinsic = origin within the tongue, but an insertion outside the tongue (i.e. larynx)
32
Q

Describe the contents between the muscle fibres in the tongue

A

Connective tissue containing fat and minor salivary glands that open by ducts to the epithelial covered surface of the tongue

33
Q

What is located between the floor of the mouth and the tongue

A

Sublingual gland, a major salivary gland

34
Q

Describe the epithelium of the dorsal surface of the tongue

A

Partially keratinized, modified in the form of papillae (projections from the surface)

35
Q

4 types of tongue papillae

A
  1. Filiform (threadlike) papillae
  2. Fungiform (mushroom shaped) papillae
  3. Foliate papillae
  4. Circumvallate papillae
36
Q

Tastes that utilize G-protein coupled membrane receptor pathways

A
  • Bitter
  • Sweet
  • Umami
37
Q

Tastes that utilize ion channels

A
  • Sour (acid) = proton channel
  • Salt = sodium channel
38
Q

Most numberous type of papillae on the tongue

A

Filiform papillae

39
Q

Reason for the tongue’s whitish velvety appearance and feel

A

Filiform papillae (keratinization of the epithelium)

40
Q

Disrtibution of filiform papillae on the tongue

A

Fine ros on either side of the central line bisecting the tongue

41
Q

Describe the histology of filiform papillae

A

Cup-shaped or pointed projections of epithelial cells that are usually keratinized on the outside, but not on the inside. Keratinization takes place from a stratum granulosum layer where the granules are eosinophilic.

42
Q

What do the eosinophilic granules of the stratum granulosum layer in the filiform papillae resemble?

A

Resemble the trichohyalin granules seen in the internal root sheath of the fair follicle

43
Q

Describe the filiform papillae in animals such as the cat

A
  • Very well-developed
  • Keratinized surface forms a sharp-ended structure with the sharp tip directed posteriorly = raspy feel to tongue and provides pockets that fill with fluid (lap up liquids)
44
Q

Describe the distribution of fungiform papillae on the tongue

A

Between the filiform papillare as small ret dots and are more numerous on the sides and tip of the tongue

45
Q

Describe the histology of fungiform papillae (5)

A
  • Mushroom-shaped
  • Lined by a stratified squamous epithelium (non-keratinized)
  • Taste buds on top
  • Core = lamina propria (primary connective tissue papilla)
  • Smaller interdigitated papillae with epithelial papillae = LP close to surface –> red
46
Q

Define foliate papillae

A

Folds in the mucosa (rather than actual papillae)

47
Q

Location of foliate papillae

A

Predominantly in the posteriolateral portions of the tongue

48
Q

Describe the development of foliate papillae from birth

A

Taste buds are present only in the newborn and soon degenerate, as do the papillae

49
Q

What empties into the base of the furrows of foliate papillae

A

Von Ebner glands

50
Q

How is the tongue divided postero-anteriorly?

A

Anterior two thirds divided from the posterior third by a V-shaped line of papilae, the lingual V.

51
Q

Describe the form of the lingual V

A

The apex of the V is directed posteriorly and the arms of the V are formed by 8 - 12 very large circumvallate papillae

52
Q

What is behind the apex of the lingual V

A

A blind invagination called the foramen caecum

53
Q

What is the foramen caecum?

A

The rudiment of the thyroglossal duct, which is the origin of the epithelial invagination from which the thyroid gland developed

54
Q

Describe the general structure of circumvallate papillae

A
  • Large structures with a large primary papilla and numberous secondary connective tissue papillae
  • Extend just above the surface of the tongue, surroudned by deep crypts
55
Q

Describe the walls of the crypts surrounding circumallate papillae

A

The side walls are formed by other tongue papillae on the outside and the smooth walls of the circumvallate papillae themselves, both of which have numerous taste buds in the epithelium.

56
Q

How do the taste buds of circumvalalte papillae open into the crypt lumen?

A

Taste pores

57
Q

Describe how the taste buds in the walls of the circumvallate papillae are stimulates

A

Substances dissolved in the saliva enter the crypt space and stimulate the sensory cells

58
Q

What happens to the fluid in the crypts of the circumvallate papillae

A

Continuous replacement by serous secretions delivered to the bottom of the crypt by way of numerous ducts from serous glands found under the circumvallate papillae

59
Q

Location of Von Ebner glands

A

Under the circumvallate papillae

60
Q

Histological location of taste buds

A

From the basal lamina through the epithelium to the surface

61
Q

What forms the taste pore of taste buds?

A

Squamous epithelial cells

62
Q

4 types of cells in the taste bud

A
  • Columnar
    • Type I dark supporting cells
    • Type II light neuroepithelial cells
    • Type III intermediate cells
  • Basal cell (type IV)
63
Q

Location of the cells types I to III in the taste bud

A

From the base of the taste bud, with their microvilli opening into the taste pore

64
Q

Location of the nuclei of the columnar taste bud cells

A

Central regions

65
Q

Location of Type IV basal cells in taste bud

A

Peripheral to the columnar cells and does not reach the taste pore

66
Q

Function of Type IV basal cells in taste bud

A

Stem cell that renews the other cells

67
Q

Turnover of taste bud cells

A

10 days

68
Q

Descirbe the support cells for the taste buds

A
  • Secretory
  • Contain secretion granules with a content that resembles the amorphous material surrounding the microvilli in the taste pore
69
Q

Number of neuroepithelial cells per taste bud

A

4 - 20 per taste bud

70
Q

Location of neuroepithelial cells of the taste bud

A

Dispersed throughout, between the supporting cells

71
Q

Contents of neuroepithelial cells of the taste bud

A

Vesicles that resemble synaptic vesicles, which are related to the free nerve endings that enter the taste bud through the basal lamina

72
Q

Describe the stimulation of taste buds

A

Substances dissolved in the saliva stimulate the sensory hairs (microvilli) and the impulse produced is conducted to the nerve endings

73
Q

Function of Von Ebner glands

A

Removal of the stimulatory substances from the taste buds