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Flashcards in GI Histo Deck (75):
1

space between lip, cheeks, and teeth

Vestibule

2

hard and soft palates, tongue, floor of mouth, and entrance to oropharynx

Oral cavity proper

3

What are the 3 types of mucosae in the oral cavity

Masticatory: SSE keratinized or parakaratinized
(mucosa on gingiva and hard palate)
Specialized: SSE keratinized
(dorsum of the tongue)
Lining: SSE non keratinized

4

What makes the specialized mucosa specialized?

Different/unique types of papillae

5

Strengthen mucosal stability of masticatory mucosa

Deep papillae from the underlying lamina propria

6

what is the distribution of papillae on the tongue?

-Ant 2/3 tongue = filiform with scattered fungiform
-Divides the ant 2/3 from the post 1/3—there are 8-12 circumvallate papillae in a row
-on lateral edges of tonge: foliates

7

Papillae on tongue that does not have taste buds

Filiform (fount on ant 2/3—the taste buds are found in the fungiform papillae in this area, they are scattered among the filiform)

8

Papillae on tongue that is keratinized

Filiform and some fungiform

9

What are the cells found in taste buds?

Sensory, supporting, and basal

10

Predominate cell type in a taste bud

Sensory

11

Cells in the taste bud that synapse with afferent nerve fibers

Sensory

12

What are the known tastes

Sweet, salt, bitter, umami

13

What is umami??

The taste of L-glutamate in monosodium glutamate (MSG) and asparagus

14

T or F: a sensory cells has a heterogenous mixture of sensory receptors

F: each sensory cell contains only 1 receptor type

15

T ort F: taste buds contain a heterogenous mixture of sensory cell types

T

16

What type of taste is generally limited to the back of the tongue

Bitter
**all others are distributed all over the tongue

17

Other than the tongue where are taste buds also found?

Roof of mouth
Posterior tongue
Epiglottis
Esophagus
pharynx

18

What are the major salivary gands?

Parotid, submandibular, and sublingual

19

Where are the minor salivary glands found?

CT of the cheek, tongue, and palate

20

What are the cell types in salivary gands?

Serous (pink) and mucous (blue)

21

What do the serious cells in salivary glands secrete?

Water substance with protein, amylase, and lysozyme

22

Describe the structural organization of the salivary glands

Acini of mucosal cells or serous cells covered in myoepithelical cells that when contracted will force secretions of acini into intercalated ducts and striated ducts

23

What is the difference between intercalated ducts and striated ducts?

Intercalated ducts are simple cuboidal and secrete and abs to modify secretion

Striated ducts are simple cuboidal to simple columnar and striations are caused by basal plasma membrane and aldso modify secretions
??? not too sure need to wiki

24

Aka for excretory ducts of salivary glands

Interlobular ducts
**do not modify secretions

25

Distinctions of the 3 salivary glands (types of acini)

Parotid is purely serous acini
Submandibular is mixed but mostly serous
Submandibular is mixed
Sublingual is mixed but mostly serous

26

What is a serous demilune and what gland(s) contain it?

In submandibular glands: serous cells forming a cap over the mucinous acini

27

Buffers content in oral cavity

Bicarb
**in saliva

28

Digestive enzymes present in saliva

Amylase and lipase

29

Role of saliva in health of teeth

Has protein that forms a protective film
Contains Ca and PO4 for minetalization of teeth

30

Are Abs preset in saliva

Yes

31

Controls mucosal movement, vascular diameter, secretion of mucosal and submucosal glands of GI tract

Submucosal plexus

32

What are the 4 concentric layers of the wall of the alimentary canal

Mucosa, submucosa, musclaris externa, serosa/adventitia

33

3 principal functions of the mucosal layer of the GI tract

1. Secretion (lubrication and digestive enzymes)
2. Absorption (vit, H2O, electrolytes, bile, cholesterol, important metabolic substrates)
3. Protection: (barrier)

34

Functions of submucosa of GI tract

Contains blood and lymph vessels, nerve plexus, occasional glands

35

Functions of the muscularis externa

Inner circular layer contracts to compress and mix contents while outer longitudinal layer contracts to propel food
= peristalsis

36

Forms sphincters along digestive tract

Inner circular layer

37

Describe the epithelium of the esophagus

SSE nonkeratinized

38

Contains GALT

Muscosa

39

Contains esophageal cardiac glands

Mucosa (mucous glands at upper and lower esophagus)

40

Contains mucous secreting tuboaveolar glands

Submucosa

41

Contains esophageal glands proper

Submucosa

42

type of muscle in muscularis externa in the esopagus

skeletal (upper 1/3) and smooth (lower 2/3)
(voluntary to involuntary)


43

what are rugae

large longitudinal gastric folds that assist in digestion (mucosa and submucosa)

44

What type of epithelium lines the stomach

columnar epithelium

45

in what later are gastric glands found?

lamina propria of the mucosa

46

forms the core of the rugae

submucosa

47

what are gastric pits?

invaginations of mucosal surface into the lamina propria forming "holes" in the gastric surface

48

what does surface mucosal cells produce?

alkaline mucous to protect stomach lining
**in large mucinogen granules

49

has acidophillic granules and secrete pepsinogen

chief cells

50

are acidophillic and secrete HCl

parietal cells

51

what cells secrete intrinisic factor

parietal cells

52

enteroendocrine cells secrete gastric hormones into the ____

lamina propria (these cells are found in the gastric glands which reside in the lamina propria)

53

gastric glands secrete there secretions into the gastric lumen via the

gastric pits

54

what cells reside in the gastric glands

chief cells, parietal cells, enteroendocrine cells, stem cells, and mucous cells (at the neck of the gland)

55

large eosinophillic pyramidal shaped cells

parietal cells

56

chief cells are (acidophillic or basophillic)

basophillic

57

where are the stem cells of the stomach found?

isthmus (new cells will move up to become mucos cells are move down to become gland cells

58

do parietal, chief cells, or enteroendocrine have a longer life span?

parietal (6 mos) > chief cells and enteroendocrine (3 mos)

59

diff between rugae and gastric glands/pits

rugae are elevations that contain mucosa and submucosa whereas pita are just invaginations of the mucosa only

60

what are the 4 modifications of the intestinal wall that allows it to increase surface area for absorption

1. plicae circulares
2. villi
3. crypts of lieberkuhn
4. microvilli

61

What are plicae circulares

transverse folds in mucosa that have a core of submucosa (increases SA 3 fold)

62

in what section of the small intestine are the plicae circulares more common

jejunum

63

villi increase the SA ___ fold and microvilli increase SA ___ fold

villi = 10 fold
microvilli = 100 fold

64

Surface epithelium has indentations (arrows) that lead to

crypts of lieberkun

65

what causes the movement of the microvilli?

actin contracts to contract terminal wweb and spread the microvilli

66

the primary absorptive cell, found on the villi, the general surface and in the glands

enterocytes

67

enterocytes are attached to neighboring cells by

tight junctions

68

in the glands, the enterocytes also secrete

water and electrolytes

69

found in the base of crypts, basal basophilia, intensely acidophilic granules in the apical region !

paneth cells

70

what do paneth cells secrete?

lysozyme (digests bacterial cell wall) and other anti-bacterial surfaces

71

overlie lymphatic nodules!

M cells

72

comprise most cells in the lower half of the gland!

intermediate cells (stem cells)

73

cells in the epi of the small intestine that can phagocytose certain bacteria and protozoa

paneth cells

74

endocytose microorganisms and macromolecules from intestinal lumen and discharge them into the underlying lymphatic tissue

M cells

75

stopped at pg 25

lamina propria of SI