9 Digestive System Oral Cavity

Question 1

What are the 3 major components of the mucosa layer?

Answer 1

epithelium
lamina propria
muscularis mucosa

Question 2

What mucosa layer has blood vessels, lymphatic vessels, and can contain glands and MALT?

Answer 2

Lamina propria [note the submucosa layer also contains these same things]

Question 3

What is the difference between stratified squamous and simple columnar epithelium in terms of function?

Answer 3

one is protective and the other is absorptive

Question 4

Where is the muscular is mucosa absent in the digestive tract?

Answer 4

oral cavity and the anal canal

Question 5

What is the connective tissue classification of lamina propria?

Answer 5

loose connective tissue

Question 6

what is the classification of the CT found in submucosa?

Answer 6

dense irregular

Question 7

What is found in the submucosa and contains the SNA and paraSNA innervations for the muscular is mucous, neuroendocrine cells and enzyme secreting cells?

Answer 7

Meissner’s plexus

Question 8

What disease is when sections of the distal colon lack meissners and auerbach’s plexus? what does it effect?

Answer 8

hirschprungs

–smooth muscle in the affected region of bowel cannot relax—>constipation and megacolon

Question 9

What are the layers of the muscular is extern?

Answer 9

• inner circular layer
• auerbach’s plexus (myenteric)
• Outer longitudinal

Question 10

What is the adventitia largely made from?

Answer 10

loose irregular connective tissue

Question 11

When does the GI system have serosa?

Answer 11

when it is covered by a peritoneal mesothelium [retroperitoneal portions don’t have this]

Question 12

What locations in the mouth are made of lining oral mucosa?

Answer 12

Lip and soft palate

bottom of tongue

Question 13

What locations in the mouth is made of specialized oral mucosa?

Answer 13

Dorsal part of tongue

Question 14

What locations in the mouth is made of masticatory oral mucosa?

Answer 14

hard pallet and gingiva

Question 15

What oral mucosa type has keratinized or parakeratinized epithelium?

Answer 15

masticatory and the specialized epithelium of the dorsal tongue

Question 16

T-F–the dorsal part of the tongue is non-keratinized?

Answer 16

false—it is keratinized

Question 17

What oral mucosa type is more susceptible to oral squamous cell carcinoma?

Answer 17

lining mucosa– floor of mouth, lateral tongue, soft palate

Question 18

What is aphthous stomatitis?

Answer 18

canker sores—ONLY IN LINING MUCOSA

Question 19

What epithelial layer does cold sores from herpes effect?

Answer 19

keratinized epithelium

Question 20

Which tongue papillae, most numerous, no taste buds, very thick keratin layer? purpose?

Answer 20

Filiform
mechanical purpose (grip like) think cow's tongue

Question 21

What tongue papillae is less numerous and irregularly arranged, taste buds, lightly keratinized?

Answer 21

fungiform

Question 22

What tongue papillae, 7-12 papillae in front of terminal sulcus, contain taste buds, contain von Ebner glands to clear old taste?

Answer 22

circumvallate

Question 23

What tongue papillae is poorly developed in humans, contain taste buds, located in posterior-lateral surface of tongue?

Answer 23

Foliate

Question 24

What is the pathway of molecule within the saliva to form a taste sensation?

Answer 24

taste pore—> gustatory microvilli –> gustatory cell depolarization—>CN VII and IX

Question 25

How many deciduous teeth are there?

Answer 25

20--shed from 6 months and 20 years of age

Question 26

What is the portion of the tooth above the gum covered by enamel?

Answer 26

crown

Question 27

What is the portion of the tooth within the alveolus surrounded by cementum?

Answer 27

Root

Question 28

What is the junction of the crown and root?

Answer 28

cervix

Question 29

What is the space within the tooth filled with soft tissue, composed of a coronal chamber and a radicular canal?

Answer 29

Pulp cavity

Question 30

What is a calcified material surrounding the pulp cavity?

Answer 30

Dentin

Question 31

What is connective tissue that joins the cementum to the alveolus?

Answer 31

periodontal ligament

Question 32

What is the hardest tissue in the body and made of 98% hydroxyapatite? What is it deposited by?

Answer 32

- enamel | - Tome's processes of ameloblasts

Question 33

Is enamel renewable?

Answer 33

No

Question 34

What is the percent calcium hydroxyapatite of dentin? What are its organic components

Answer 34

70% | --Type I collagen fibers and GAGs [secreted by odontoblasts]

Question 35

What are tall cells that line the pulp cavity that secrete a collagen rich matrix from their apical surface known as predentin?

Answer 35

odontoblasts

Question 36

What are canals in which odontal processes run called? | How long are they?

Answer 36

- dentinal tubules | - The length of the span of dentin

Question 37

What is the makeup of pulp?

Answer 37

- mesenchyme-like CT - blood vessels - nerves (via apical foramina in tooth root)

Question 38

What are pulp nerve fibers sensitive to?

Answer 38

temperature and pH which is interpreted as pain

Question 39

What structures make up the periodontium?

Answer 39

cementum periodontal ligament alveolar bone gingiva

Question 40

What is the region of the tooth where the enamel crown ends and the cementum layer surrounding the root begins?

Answer 40

cement-enamel junction

Question 41

Where is the cementum the thickest?

Answer 41

apical region

Question 42

What produces cementum? where are they located?

Answer 42

cementocytes in the periodontal ligament

Question 43

T-f----cementum can react to stresses by resorbing tissue or laying down new cementum?

Answer 43

True

Question 44

What has the appearance of primary immature bone, contains osteocytes within the lacuna and helps hold the teeth in place?

Answer 44

alveolar bone

Question 45

What structure does scurvy largely effect?

Answer 45

synthesis of collagen and especially effects the periodontal ligament

Question 46

When does teeth formation occur? how long does it take for a tooth to develop?

Answer 46

6 weeks | 14 months

Question 47

What is the order of stages for tooth development?

Answer 47

bud--->cap---> bell

Question 48

What are the main structures found in the bud stage?

Answer 48

dental lamina [ectoderm] and dental bud [ingrowth of the dental lamina]

Question 49

What stage is marked by the invagination of the dental bud and engulfing of a region of ecto-mesenchyme?

Answer 49

cap stage

Question 50

What 2 main structures make up the cap stage?

Answer 50

1. dental follicle [cap and ectomesenchyme] | 2. dental papilla [portion of ectomesenchyme that is immediately surrounded]

Question 51

What are the layers surrounding the dental papilla called?

Answer 51

enamel organ

Question 52

What are the layers of the enamel organ?

Answer 52

- inner enamel epithelium - stellate reticulum - outer enamel epithelium

Question 53

What cells will differentiate by reciprocal induction to form ameloblasts?

Answer 53

Inner enamel epithelium

Question 54

The cells of the dental papilla differentiate to form?

Answer 54

odontoblasts and pulp

Question 55

What forms from the dental lamina cells closest to the enamel organ?

Answer 55

odontoblasts

Question 56

What are the layers of the forming tooth from the stellate reticulum inward?

Answer 56

``` stellate reticulum ameloblasts enamel dentin predentin odontoblasts pulp ```

Question 57

In reciprocal induction, the enamel organ induces the dental papilla to form what?

Answer 57

odontoblasts an produce dentin

Question 58

In reciprocal induction, the forming dentin induces the enamel organ to form what?

Answer 58

ameloblasts which secrete enamel

Question 59

Does root formation occur before or after crown is completed?

Answer 59

After