Oral and Esophageal Histology

Question 1

Describe the general structural plan in the GI system?

Answer 1

1. mucosa
2. submucosa
3. supporting wall
4. adventitia/serosa

Question 2

What are the three general surface areas/features for the lip?

Answer 2

1. an outer cutaneous layer (skin)
2. red area
   3 oral mucosa

Question 3

What’s the supporting wall for the lip?

Answer 3

orbicularis oris muscle

Question 4

What is the supporting wall for the cheek?

Answer 4

the buccinator

Question 5

The mucosa and submucosa of the cheek is similar to that of the lips except for what difference?

Answer 5

there’s more elastic tissue in the submucosa of the cheek to help reduce biting your cheeks

Question 6

Where in the mouth is the stratified squamous epithelium keritinized and where is it not?

Answer 6

in general it’s keritinized in areas where there’s lots of stress from eating. So on the top of the tongue and on the hard palate it’s keritinized.
On the lips and lower part of the tongue it’s non-keritinized

Question 7

Describe the submucosa of the hard palate and explain how it differs in different areas.

Answer 7

it’s absent in the midline
anterior 1/3 has lots of fat
posteiror 2/3 has lots of mucous glands

Question 8

Describe the epithelium for the soft palate.

Answer 8

it’s stratified squamous keratinizing on the oral side and then pseudostratified columnar ciliated on the nasal side

Question 9

Describe the submucosa of the soft palate.

Answer 9

it’s mostly mixed glands

Question 10

What’s the supporting wall of the soft palate?

Answer 10

skeletal muscle and connective tissue

Question 11

Why is the dorsal surface of the tongue’s mucosa complex?

Answer 11

its lamina propria is modified to form various papillae

Question 12

The serous glands are beneath what papillae?

Answer 12

the circumvallate papillae

Question 13

What do the mucous lgands empty into on the dorsal tongue?

Answer 13

tonsillar crypts

Question 14

What nerves supply the anterior 2/3 of the tongue?

Answer 14

cranial nerves V and VII

Question 15

What nerves supply the posterior 1/3 of the tongue?

Answer 15

cranial nerves IX and X

Question 16

What are the 4 types of tongue papillae?

Answer 16

filiform
fungiform
circumvallate
foliate

Question 17

What’s the most numerous papillae?

Answer 17

filiform

Question 18

What’s the papillae that sticks up higher than the rest?

Answer 18

fungiform

Question 19

Which are underdeveloped in humans?

Answer 19

foliate - located on the lateral sides of the tongue

Question 20

On histology, why are filiform papillae really obvious/

Answer 20

they have lots of obvious keratinization

Question 21

Where on the tongue are fungiform papillae most numerous?

Answer 21

towards the tip

Question 22

What do the fungiform papillae look like?

Answer 22

slightly reddish club-shaped

Question 23

What crnaial nerves innervates the fungiform papillae?

Answer 23

cranial nerve VII

Question 24

What papillar are adjacent to the sulcus terminalis?

Answer 24

circumballate

Question 25

What surrounds the circumvallate? What empties there?

Answer 25

a deep trench in which the serous glands of von Ebner empty

Question 26

What cranial nerve supplies the circumvallate papillae?

Answer 26

CN IX

Question 27

Taste buds are on what papillae?

Answer 27

circumvallate fungiform foliate NOT on filiform

Question 28

What layer are the taste buds embedded in?

Answer 28

epithelial layer

Question 29

What are the three types of cells within taste buds?

Answer 29

sustentacular cells taste receptor cells basal cells (which give rise to the other 2)

Question 30

WHat's the outer layer of a tooth?

Answer 30

enamel?

Question 31

What's the middle layer that surrounds the pulp cavity?

Answer 31

dentin

Question 32

What produces enamel?

Answer 32

ameloblasts

Question 33

What produces dentin?

Answer 33

odontoblasts

Question 34

What is the collagenous fibers with nerves that sort of act like a sling to keep the tooth in place?

Answer 34

the periodontal ligament

Question 35

What connects the tooth to the periodontal ligament?

Answer 35

the cementum (formed by cementoblasts)

Question 36

What type of bone does the periodontal ligament connect the tooth to?

Answer 36

alveolar bone - cancellous bone

Question 37

What are the three major salivary glands?

Answer 37

parotid submandibular sublingual

Question 38

What is the composition of saliva?

Answer 38

Water, cellular & bacterial debris, leukocytes, salts, salivary amylase, mucus, secretory IgA, desquamated epithelial cells

Question 39

In general, what are the 4 ducts of a salivary gland?

Answer 39

excretory duct striated duct intercalated duct alveolus

Question 40

What are the specialized smooth muscle cells between serous/mucous cells and basement membrane in the secreotry unit?

Answer 40

myoeptihelial cells

Question 41

What do myoepithelial cells do?

Answer 41

they contract to help discharge from the secretory cells

Question 42

What epithelium is typically in the lumen of an excretory duct?

Answer 42

stratified columnar

Question 43

How do excretory ducts differ from the striated?

Answer 43

excretory are bigger and striated are more eosinophilis

Question 44

How do the striated duct differ from the intercalated?

Answer 44

intercalated area really tiny

Question 45

Which are darker staining, mucous or serous alveoli?

Answer 45

serous are dark, mucous are light (plus mucous has nuclei at the outer edge)

Question 46

What's the cap that ou occasionally see on a mucous alveolus?

Answer 46

a serous demilune

Question 47

What surrounds a parotid gland?

Answer 47

a very prominent connective tissue capsule CT separating lobes and lobules

Question 48

True or false: striated and itnercalated ducts are prominent in the parotid gland.

Answer 48

true

Question 49

Are acini primarily serous or mucous in the parotid gland

Answer 49

almost 100% serous

Question 50

What additional tissue is found surrounding the acini and ducts of the parotid gland?

Answer 50

fat

Question 51

Is the CT capsule more or less present in the submandibular gland compared to the parotid?

Answer 51

less conspicuous than the parotid

Question 52

What ducts are well defined and which are scarce in the submandivulra/

Answer 52

striated are well defined while intercalated are scarce

Question 53

What are the acini mostly in the submandibular

Answer 53

most are serous, but 10-25% are mucous

Question 54

How does the CT capsule of the sublingual compare?

Answer 54

very indistinct

Question 55

What ducts are prominent and what are not in the sublingual

Answer 55

excretory ducts prominent while striated are not prevalent and intercalated are non-existent

Question 56

What are most of the acini in the subligual gland?

Answer 56

75% are mucous with serous demilunes and 25% are serous

Question 57

What are the layers of the esophagus?

Answer 57

mucosa submucosa musclaris externa adventitia

Question 58

What glands are located in the upper 1/3 and lower 1/3 of the esophageal mucosa?

Answer 58

mucous glands called cardiac glands

Question 59

Where are the mucous glands in the middle 1/3 of the esophagus?

Answer 59

in the submucosa

Question 60

What else is located in the submucosal layer for the esophagus?

Answer 60

the submucosal nerve plexi | larger blood vessels and lymphatics

Question 61

What type of muscle is in the muscularis externa?

Answer 61

skeletal muscle for the first 1/3, both in the middle and then smooth in the lower 1/3

Question 62

What else is located in the muscularis externa?

Answer 62

myenteric nerve plexi

Question 63

Does the esophagus have a serosa or an adventitia?

Answer 63

adventitia