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Histology Exam III Material > Upper GI I > Flashcards

Flashcards in Upper GI I Deck (133):
1

What kind of epithelium lines most of the GI tract

Simple columnar epithelium with glands for most of the tract

2

Musculature of the GI tract

- skeletal muscle at either end and also in the esophagus
- Smooth muscle throughout most GI

3

The GI tract possesses an ______ rhythmicity

intrinsic

4

The GI tract possesses an intrinsic rhythmicity mostly due to the presence of

enteric nervous system

5

The enteric nervous system exists independently of

external influences including the ANS

6

The GI tract has Enteric nervous system (which is independent) but also receives input from

sympathetic and parasympathetic nervous systems

7

What are the peptide neurotransmitters

- Bombesin
- Motilin
- Vasoactive intestinal peptide

8

Unicellular endocrine cells secrete

neuropeptides

9

Unicellular endocrine cells are derived from

endoderm (which is unlike intrinsic nerve fibers, which are derived from neural crest)

10

Intrinsic nerve fibers are derived from

neural crest

11

What is MALT

mucosal associated lymphoid tissue

12

What is GALT

gut associated lymphoid tissue

13

Protective mechanisms of GI include

Production of large amounts of mucous: which assists in lubrication and friction reduction

Rapid turnover of epithelial cells in harsh environments such as the stomach and small intestine

14

The oral cavity is lined with a mucous membrane lying on a _________ layer

Vascular FECT layer

15

The mucosa of the lip consists of

-Stratified Squamous epithelium
- Basement membrane
- Lamina propria

16

The lip is composed of a core of ___________ cells embedded in FECT and covered externally by skin

skeletal muscle cells (obicularis oris)

17

Within the lamina propria of the lip are ____ and ____ glands

mixed and mucous glands

18

The dermis of the lip has a rich plexus of _____ which prominent at the ______ of the lip

capillaries, free margin

19

Internally the lip is lined with ____ keratinized, modified, _________ epithelium lies on a lamina propria with _______ papillae

Poorly, stratified squamous epithelium, high papillae

20

What is the one exception that makes the cheeks structure different than the lip

the cheek has abundant elastic fibers in the submucosa
- These are continuous with the fibers surrounding the striated muscle and the lamina propria
- This arrangement give a maximum of distensibility to the oral mucous membrane

21

What gives the cheek's oral mucous membrane maximum distensibility

abundant elastic fibers in the submucosa are continuous with the fibers surrounding the striated muscle and the lamina propria

22

what three embryonic tissues interact in the development of the teeth

Ectoderm- which forms the enamel organ
Neural crest and mesoderm give rise to the dental papilla

23

ectoderm forms what part of the teeth? and influences the development?

-enamel organ
- Consists of cells committed to formation of enamel
- Formed from ectoderm under influence of mesoderm and neural crest

24

Neural crest and mesoderm give rise to dental _____. Which is

Dental papilla
- dentin
- Cementum
- Pulp
- surrounding CT and periodontal pulp

25

________ is formed from basal cells of the oral ectoderm

dental primordium

26

The _________ is an epithelial shelf that grows from the thickened primordial into mesenchyme as a bifid structure

labiodental lamina

27

The external limb splits later to form a groove that deeps to separate the _____ and the remainder of the _____

lip, mouth

28

In the development of the teeth the internal limb is the

dental lamina

29

in the development of teeth cells proliferate to form the _______ in each half-jaw

tooth buds (germs)

30

In the development of teeth a second set of tooth-buds develops on the _____ side of each developing deciduous tooth plus three more ______ in each half-jaw

lingual, posteriorly

31

The epithelial bud becomes what parts of the teeth

Enamel organ
Dental papillae
Dental sac (follicle)

32

The enamel organ forms ______ and caps the _____

Enamel, and caps the dental papilla

33

Condensation of mesenchyme that gives rise to dentin and pulp

Dental papilla

34

CT sac that surrounds the enamel organ and dental papilla and forms cementum and the periodontal membrane

Dental sac (follicle)

35

Cells involved in tooth development

Odontoblasts, Ameloblasts

36

_____ form the dentin matrix throughout the life of the tooth

Odontoblasts

37

_____ form single layer of cells lining pulp cavity

odontoblasts

38

Cytoplasmic extensions of the odontoblasts continuing through the prevention and dentinal layers to the dentin-enamel junction; they occupy a space in the dentin matrix known as dentinal tubules

Tomes' dentinal fibers (odontoblastic processes)

39

Dentin is similar to bone but is _____: ___% of matrix is organic (compared to about 35% in bone) and composed mostly of _______

harder, 35% and composed mostly of collagen type I

40

Increment lines (of Ebner and Owen) are associated with

Odontoblasts

41

Ameloblasts form _____ which covers only the tooth crown

Enamel

42

____ is the hardest substance in the body

enamel

43

Enamel is ____% inorganic salts, about ____ % of which is calcium phosphate in the form of aptitude crystals and ___% organic matter and water

96%, 90%, 4%

44

Enamel is 96% _____, about 90% of which is _______ in the form of _______ and 4% _____ and _____

inorganic salts, calcium phosphate in the form of apatite crystals, organic matter and water

45

Enamel is laid down in _____, each of which is formed by one _____

prisms, ameloblast

46

Each prism is formed by one ____

ameloblast

47

The secreting apical domains of ameloblasts are called

Tomes' processes

48

Ameloblasts are associated with _________ which are periods of rhythmic growth

increment lines of Retzius

49

Specific organic components, rather than collagen, are unique to enamel and are removed after calcification

Amelogenins
Enamelins

50

Originates form the dental papilla containing condensed mesenchyme

Pulp

51

Teeth pulp consists of

fibroblasts, macrophages, peripheral odontoblasts, reticular fibers, nerve fibers, and blood vessels that pass via the apical foramen

52

Cells of the dental sac differentiate into ______ which deposit cementum on the dentin of the root from neck to apex.

Cementoblasts

53

Cementum has coarse ______(_____) in a bone-like calcified matrix

Collagen fibers (Sharpey's)

54

Peridontal membrane is highly _______ active tissue

metabolically

55

CT formed from dental sac with fibroblasts, osteoblasts, cementoblasts, collagen fibers, blood vessels, and nerve fibers

Peridontal membrane

56

Peridontal membrane binds _____ to ______

cementum to bony socket

57

Sharpey's fibers extend form centum to _____ via the ______

Alveolar wall via the periodontal membrane

58

Peridontal membrane allows _____ movement

limited

59

Periodontal membrane absorbs ______ and prevents

absorbs pressures of mastication and prevents this pressure form damaging alveolar bone

60

Periodontal membrane is affected by diseases such as ______ and _____

diabetes and scurvy

61

The tongue is composed primarily of a core of _____ and ______, and is covered by a ________

Skeletal muscle and glands, and is covered by a mucous membrane

62

The anterior two-thirds of the upper oral portion is separated form the posterior one-third of the tongue by the ________

sulcus terminalis

63

______ appear on the oral portion of tongue as surface projections

Lingual papillae

64

Lingual papillae are formed of a ________ covered by ________ epithelium

central core of CT lamina propria covered by stratified squamous epithelium

65

What are the most numerous of all the papillae

filiform papillae

66

What type of papillae lack taste buds

filiform papillae

67

Filiform papillae are _____ distributed over the _____ portion of tongue

evenly, entire oral upper portion

68

_______ papillae are the most numerous of all the papillae and have a ______ appearance

Filiform papillae, conical

69

What is the function of filiform papillae

gives tongue a rough surface

70

Fungiform papillae have a ______ appearance

mushroom

71

Fungiform papillae are ______ in numer

relatively few

72

Fungiform papillae are interspersed _____ among the _______ rows of ______

singly among the parallel rows of filiform papillae

73

Taste buds of fungiform papillae are present

only on the oral surface of the epithelium

74

Taste buds of the circumvallate papillae are located

primarily in the lateral walls

75

Type of papillae that is rudimentary in humans, but well developed in lower animals

Foliate papillae

76

Circumvallate papillae are located along the _____ as _____ surrounded by a ____

sulcus terminalis as projections surrounded by a moat (circular furrow)

77

_______ open into the moat of Circumvallate papillae

Ducts of Von Ebner's glands

78

The _______ portion of the tongue is free of papillae but contains the lingual tonsils

pharyngeal

79

The pharyngeal portion of the tongue is free of ______ but contains the _______

Papillae, lingual tonsils

80

Taste buds of circumvallate papillae are located

on the lateral walls

81

Taste buds contain contain ____ types of cells derived form a _________

two, single stem cell

82

what are the two types of cells in a taste bud

sustentacular cells
taste cells

83

Spindle-shaped support cells and arranged like barrel-staves to surround the inner taste pro at the base

Sustentacular cells

84

Each taste cells is long and slender with an elongated _______ and terminates as a short taste hair which projects into the external opening called the

Central nucleus, outer taste pore

85

Taste cells possess apical ____ with ______ and the basal part of the cell releases ______

microvilli with taste receptors, neurotransmitters

86

Taste cells are distributed

between the supporting (sustentacular) cells

87

Except for ____ taste, taste sensation utilize various ________ pathways that result in depolarization of the taste cells

bitter, signal transduction pathways

88

salt and sour taste utilize ____ transport as a signal transduction mechanism

Ionic

89

Sour tast involve _____ blockage of ______ to cause depolarization

hydrogen ion blockage, potassium ion channels

90

Bitter taste involves a _______ state similar to _________

Hypopolarized state similar to retinal cell signal transduction

91

Sweet taste involves a _____ state

hyperpolarized state

92

Gustducin (a homologue of retinal transducin) is a G-protein used what taste receptors

Bitter and Sweet

93

Bitter and sweet taste receptors involves the activation of ______, decrease in ______, and closure of _______ and hypo polarization of the taste cell

G- alpha subunit, decrease in cGMP, and closure of sodium channels and hypolarization of the taste cell

94

What are the four type of lingual papillae

-Filiform papillae
- Fungiform papillae
- Foliate Papillae
- Circumvallate papillae

95

What are the 4 layers of digestive tube

-Mucosa (innermost)
- Submucosa
- Muscularis externa
- Outermost layer= Serosa and Adventitia

96

Characteristic of mucosa of digestive tube

-epithelium-
- Stratified squamous transitioning to simple columnar
- May have secretory, absorptive, and/or protective functions

- Lamina Propria
- Loose Areolar CT associated with epithelium
- Contains various glands and GALT

- Muscularis Mucosa
- Made up of one to three layers of smooth muscle

97

Submucosa of digestive tube

- Dense, irregular CT
- Vascularized
- Contains a nerve plexus: Meissner's plexus (submucosal plexus)

98

Muscularis external of digestive tube

-inner circular layer of smooth muscle
-outer longitudinal layer fo smooth muscle
- Myenteric (Auerbach's) nerve plexus lies between the two layers of muscle tissue

99

Location of Myenteric (Auerbach's) nerve plexus and its function(s)

Lies between the inner circular layer of smooth muscle and the outer longitudinal layer of smooth muscle, which make up the Muscularis externa

fxn:
- Regulates the size of the lumen (circular layer of smooth muscle)
- Regulates the rhythmic movement of the GI tract (longitudinal layer of smooth muscle)

100

Characteristics of Serosa of digestive tube

-composed of dense irregular CT
- Consists of mesothelial lining and a layer of submesothelial CT
- Forms visceral peritoneum
- Covers intraperintoneal portions of abdominal organs

101

What forms the visceral peritoneum

Serosa of digestive tube

102

Characteristics of adventitia of digestive tube

-Dense irregular CT with Adipose tissue
- Covers retroperitoneal portions of digestive system

103

What covers the retroperitoneal portions of the digestive system

Adventitia of digestive tube

104

Where is Meissner's plexus located

in the submucosa of digestive tube (also called submucosal plexus)

105

Sympathetic ________ pass through gut wall to glands and smooth muscle

postganglionic fibers

106

Parasympthetic ________ synapse with _______ in_____ within the gut wall itself

preganglionic fibers synapse with postganglionic fibers in ganglia within the wall itself

107

What are the two plexi of the parasympathetics in the gut wall

Meissner's plexus
Auerbach's plexus

108

Function of Meissner's plexus

regulates local secretions, blood flow, and absorption

109

Function of Auerbach's plexus

Coordinates muscular activity of gut wall

110

_____is the first line of defense and is found coating the luminal surface of the gut mucosal epithelium

IgA

111

Isolated lymph follicles in the gut are found in the

lamina propria

112

Specialized squamous epithelial cells (___) in the gut lumen serve to transport food antigens to the lymph follicles, which are in the lamina propria

M cells

113

What are M cells

Specialized squamous epithelial cells in the gut lumen serve to transport food antigens to the lymph follicles

114

Antigen stimulated _____ in the isolated lymph follicles of the lamina propria in the gut secrete ____

B cells, IgA

115

Diffuse lymphoid tissue in the lamina proper of the gut includes

lymphocytes, macrophages, and IgA-secreting plasma cells

116

Aggregated lymphoid follicles form the ____ of the oropharynx (_______) and ______ in the submucosa of the ileum

tonsils, Waldeyer's ring, Peyer's patches

117

Aggregated lymphoid follicles in the submucosa of the ileum

Peyer's patches

118

Functions of the esophagus

digestion (initiated in the mouth)
Addition of mucous to food bolus

119

The esophageal-stomach epithelial transition zone shows what change in epithelium and is a frequent site of what

stratified squamous transitions to simple columnar
frequent site of cancers

120

Mucosa of esophagus

-Stratified squamous nonkeratinized epithelium
- Mucous glands are found in the lamina propria and submucosa

121

Muscularis external of the esophagus transitions from _______ in the upper third to a mixture of ____ and ____ in the middle third and then to ____ only in the lower third

skeletal muscle, skeletal and smooth muscle, smooth

122

Surface mucous cells of the stomach secrete

protective insoluble mucous

123

Gastric mucosa consists of

simple columnar epithelium with mucous columnar cells

124

_____ ar longitudinal mucosal folds that are most prominent in an empty stomach

Rugae

125

Gastric glands open into ____

gastric pits

126

The muscularis externa of the stomach has ____ layers of -___ muscle

3 layers of smooth muscle

127

The third layer of the muscularis externa is ________ layer

inner oblique

128

What are the regions of the stomach

Cardiac, Fundus, body, Pylorus

129

The cardiac stomach contains mostly ____ glands

mucous

130

The fundus and body of stomach contains ______ glands

gastric glands

131

gastric glands are ______ glands extending down to the _______

long tubular, muscularis mucosae

132

The gastric glands are composed of

mucous neck cells
parietal cells
chief cells
stem cells
enteroendocrine cells

133

The pyloric stomach contains

mucous glands and enteroendocrine cells