Lecture 9 Flashcards Preview

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Flashcards in Lecture 9 Deck (94)
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1
Q

Epithelium is called _____ if one cell thick, _____ if more than one layer

A

simple, stratified

2
Q

Epithelium is _______ if elongated at right angles to the surface, _______ if square in profile, _______ if flattened parallel to the surface

A

columnar, cuboidal, squamous

3
Q

T/F - in stratified epithelium, cells usually divide in the layer closest to the basement membrane & then move towards the surface where they are sloughed.

A

True

4
Q

T/F - blood vessels usually penetrates epithelia with nerves

A

False, do not usually

5
Q

______ - a protective modification in stratified squamous epithelia where the surface cells consist either wholly or partly of a proteinaceous material called _____

A

keratinization, keratin

6
Q

Cells flatten as they move through the layers of epithelium & manufacture the precursors to keratin (_______ & _____)

A

tonofilaments, keratohyalin granules

7
Q

If keratinization is complete, then the ________________________ including the ____ die.

A

organelles in the superficial layers, nuclei,

8
Q

T/F - cellular structures are retained and desmosomes persist until the cells shed from the surface

A

True

9
Q

Complete keratinisation is found in regions of high wear & tear & the epithelium is described as ___________.

A

Orthokeratinised

10
Q

If keratinization is partial & some organelles & the nuclei are retained in superficial layers then the epithelium is __________.

A

Parakeratinised

11
Q

If no keratinisation occur then the epithelium is called ___________.

A

Non keratinised

12
Q

T/F - recognise orthokeratinisation by all organelles including nuclei lost

A

True

13
Q

T/F - recognise parakeratinisation with flattened nuclei but functional

A

False

14
Q

T/F - recognise non-keratinisation with nuclei retained but very flattened & inactive

A

False

15
Q

T/F - the enamel organ (an epithelial structure) incorporates capillaries during the formation of dentine & enamel

A

True

16
Q

T/F - Epithelial-connective tissue junction is a basal lamina/basement membrane that separates epithelia from connective tissue

A

True

17
Q

T/F - epithelial connective tissue junction in stratified squamous epithelia is no folded, and is usually flat.

A

False, it is folded not flat,

18
Q

Connective tissue protrusions are called ________ ______ (dermal papillae in skin).

A

Proprial papillae

19
Q

Epithelial folds between the proprial papillae are _____ ____.

A

Rete pegs

20
Q

Proprial papillae may incorporate sensory structures: _________

A

Meissners corpuscles (nerve endings plus supporting cells)

21
Q

Basement membrane is a ____ ________ structure which is immediately below the deepest cells of an epithelium.

A

thin, amorphous

22
Q

The term ___________ is used to describe a layer beneath the epithelium which has a complex composition (_______,_______) but amorphous appearance.

A

basal lamina, proteoglycans, glycoproteins,

23
Q

The term ______ _____ includes associated collagen, providing attachment & to some extent acts as a semipermeable barrier between epithelium & CT.

A

Basement membrane

24
Q

Connective tissue beneath the epidermis is called __________________________.

A

Lamina propria in mucosa & dermis in skin.

25
Q

If a second deeper layer is present in CT, it is called _________ in mucosae or hypodermis in skin.

A

Submucosa

26
Q

T/F - submucosa may contain glands &/or fat.

A

True

27
Q

T/F - Blood vessels & nerves are always a feature of the connective tissue beneath the epithelium & there may also be glands & in the case of skin, skin appendages.

A

True

28
Q

List the layers of the oral mucosa

A
  • basement membrane (basal lamina)
  • lamina propria (connective tissue)
  • sometimes submucosa (junction between mucosa and submucosa not easy to recognise)
29
Q

T/F - If submucosa is absent , the lamina propria connects directly to mucoperiosteum.

A

False, LP connects to the periosteum directly if no submucosa.

30
Q

Masticatory mucosa is located in _______ & ______.

A

Gingivae, hard palate

31
Q

T/F - masticatory mucosa is thick

A

True

32
Q

T/F - Masticatory mucosa can be ortho or parakeratinised

A

True

33
Q

Junction between epithelium & lamina propria is characterized by _____ ______ ______ & ____ ____ - to help resist shearing forces

A

deep proprial papillae, rete pegs

34
Q

Lamina propria is generally ______ ______ ______ ______.

A

Dense collagenous connective tissue.

35
Q

T/F - the gingiva has a submucosa which is firmly attached to periosteum of bone

A

False, it lacks submucosa, and mucosa attaches to periosteum of bone.

36
Q

T/F - (hard palate) submucosa is present on lingual gingivae and in midline raphe (elevation.)

A

False, submucosa is absent on lingual gingivae

37
Q

T/F - (hard palate) submucosa with fat & salivary glands is absent between gingivae & raphe

A

False, submucosa is present

38
Q

T/F - submucosa overlies palatine neurovascular bundles (greater palatine nerves, nasopalatine nerves & accompanying palatine arteries.

A

True

39
Q

Name the lining mucosa according to lovaction

A
  • Buccal mucosa
  • Labial mucosa
  • Alveolar mucosa
  • Soft palate,
  • ventral surface of tongue
40
Q

T/F - soft palate has thick mucosa, whilst buccal and labial mucosa are thin

A

False, other way around

41
Q

T/F - Lining mucosa is generally keratinized

A

False, generally non keratinized

42
Q

T/F - Lining mucosa generally has a submucosa

A

True

43
Q

T/F - Specialised mucosa is located on dorsal surface of tongue (presence of taste buds)

A

True

44
Q

T/F - Dorsal tongue has thin keratinized simple squamous epithelium

A

False, it has thick, stratified

45
Q

List the lingual papillae of dorsal tongue

A
  • filiform
  • fungiform
  • foliate
  • vallate
46
Q

T/F - lingual papillae are small elevations on the ventral surface of the tongue consisting of epithelium & some lamina propria

A

True

47
Q

Taste buds are ________ structures with cells oriented differently to the adjacent epithelium. Opening into taste bud is __________, the space beneath the pore & above the cells is the _________.

A

intraepithelial, Taste pore, taste pit,

48
Q

T/F - Taste buds are found on lingual, vallate, fungiform lingual and filiform papillae.

A

False, they are found on every papillae, except filiform.

49
Q

List the three cell types consisting in Taste buds

A
  • Neuroepithelial/sensory cells
  • Supporting cells
  • Basal cells
50
Q

T/F - Neuroepithelial sensory cells are elongated with an apical microvillus, extending from basement membrane to taste pit.

A

True

51
Q

T/F - Supporting cells are not elongated & not difficult to distinguish from the neuroepithelial cells

A

False, they are elongated and difficult to distinguish

52
Q

T/F - Only neuroepithelial cells not supporting cells have elongated nuclei & extend from basement membrane to taste pit.

A

False, both cells have these properties

53
Q

T/F - Turnover time for both neuroepithelial cells and supporting cells is about 10 days

A

True

54
Q

T/F - Basal cells are adjacent to basement membrane and extends to taste pit.

A

False, they do not extend to taste pit.

55
Q

Function of basal cells?

A

probably a reserve population of cells

56
Q

T/F - Basal cells have rounded nuclei adjacent to the basement membrane.

A

True

57
Q

The bulk of the tongue is ___________ (not cellular when fully formed). The precursor cells called _______ fuse to form a multinucleate masses of cytoplasm called ______ which are the muscle fibres. When this happens the nuclei relocate to the edges of the _______. The peripheral nuclei are used to distinguish ________ from smooth muscle which retains its cellular form with nuclei centrally positioned within the cells.

A

Skeletal muscle, myocytes, syncytia, synctium, skeletal muscle

58
Q

T/F - Serous intrinsic salivary glands

(of Von Ebner) are situated between bundles of smooth muscle.

A

False, skeletal muscle

59
Q

T/F - glands of von ebner consist of serous secreting endpieces emptying into branched ducts which open into sulci (indentations) between papillae or into vallum (moat) around vallate papillae.

A

True

60
Q

T/F - The tongue has mucous intrinsic glands which dominate the anterior part of the tongue.

A

False, they dominate the pharyngeal/postsulcal part of the tongue

61
Q

T/F - Ventral tongue is thick usually non-keratinized stratified squamous epithelium (thinner than dorsal) with a rough surface

A

False, it has a smooth surface.

62
Q

T/F - extrinsic salivary glands all develop as outgrowths from the developing oral cavity.

A

True

63
Q

T/F - Extrinsic salivary glands are all lobulated glands

A

True

64
Q

Extrinsic salivary glands consist of groups of hollow ___________________, each surrounded by a small amount of connective tissue.

A

Secretory endpieces called acini

65
Q

T/F - The epithelium of secretory endpieces consists of either serous or mucous secreting cells or a mix of the two.

A

True

66
Q

T/F - each secretory endpiece empties into a small duct, which in turn coalesce into even smaller ducts

A

False, even larger ducts

67
Q

T/F - extrinsic salivary glands ducts are lined with columnar epithelium

A

False, simple epithelium.

68
Q

Extrinsic salivary glands are collectively called _______ if they are within a lobule. They are also excretory ducts mostly located in ___________.

A

intralobular, interlobular connective tissue

69
Q

List two types of intralobular ducts:

A
  • intercalated ducts

- striated ducts

70
Q

T/F - intercalated ducts are the smallest ducts and drain the acini, having a smaller diameter than the acini.

A

True

71
Q

T/F - intercalated ducts are lined with columnar epithelium, and a number of these coalesce to form larger striated ducts.

A

False, they are lined with flattened or cuboidal epithelium.

72
Q

T/F - striated ducts are lined with cuboidal cells which stain deep pink (due to numerous mitochondria, which are also responsible for the poorly resolved striations seen in LM).

A

False, they are columnar cells

73
Q

T/F - striated ducts modify the composition of saliva.

A

True

74
Q

__________ in turn form when a number of striated ducts coalesce. They are as large or larger that the striated ducts & lack their deep pink staining. They ____________________________________.

A

Excretory ducts, run initially in the sparse intralobular connective & then through the connective tissue between the lobules.

75
Q

T/F - Excretory ducts coalesce to form the minor ducts that drain into the oral cavity or vestibule.

A

False, they form the main ducts

76
Q

_________ - a connective/fascia concentration surrounding ENTIRE extrinsic salivary gland (parotid & submandibular only).

A

Capsule

77
Q

T/F - the capsule in both parotid and submandibular glands is part of the investing layer of deep cervical fascia.

A

True

78
Q

T/F - the sublingual salivary gland is immediately below the oral mucosa and has a capsule.

A

False, it does not have a capsule.

79
Q

List the individual salivary glands

A
  • Parotid
  • submandibular
  • sublingual
80
Q

T/F - parotid gland is completely serous

A

True

81
Q

T/F - submandibular gland is mostly mucous cells

A

False, mostly serous acini plus acini with mixed serous and mucous cells

82
Q

T/F - sublingual gland is mostly serous cells

A

False, mostly mucous, some acini have a mix of serous & mucous, purely serous acini are rare

83
Q

T/F - intrinsic salivary glands within oral mucosa

A

True

84
Q

T/F - intrinsic salivary glands are classified according to location

A

True

85
Q

T/F - intrinsic glands are mostly serous except von Ebners which are mucus

A

False, they are mostly mucus, von ebners are serous

86
Q

T/F - intrinsic salivary glands have secretory acini which empty into a long duct which passes through the oral mucosa

A

False, its a short duct

87
Q

T/F - intrinsic salivary glands lack a capsule

A

True

88
Q

Lip includes skin of ______, ____ _______ & a specialized region in between skin & mucosa unique to humans called the _____ or ___ _____ or ____ ____ to the oral mucosa of the vestibule

A

face, oral mucosa, vermillion, red zone, transitional zone

89
Q

T/F - Skin is typical thick skin with thin keratinized epidermis with large skin appendages including hair follicles, sbeaceous glands & sweat glands.

A

False, they had small skin appendages,

90
Q

List properties of oral mucosa

A
  • thick non keratinized epithelium
  • dense underlying lamina propria
  • minor salivary glands in lamina propria/submucosa
91
Q

Describe Vermillion Zone

A
  • thin lightly keratinized epithelium
  • deep dermal papillae with numerous blood vessels which give the vermillion zone its characteristic colouration & specialized nerve endings which perceive touch.
  • absence of sweat glands & hair follicles,
  • few sebaceous glands,
92
Q

T/F - Lip skeletal muscle exists in deep part of lip between skin and mucosa.

A

True

93
Q

T/F - mostly orbicularis oris moves lip

A

True

94
Q

List the age changes in oral mucosa (4 changes)

A
  • oral mucosa may thin with reduction of rete pegs
  • reduction in number of filiform papillae
  • atrophy of some of the intrinsic salivary glands
  • changes due to tooth loss or wear or wearing dentures or to medications