Oral Cavity And Esophagus

Question 1

What are the layers of the alimentary canal from internal to external?

Answer 1

Mucosa
Submucosa
Muscularis externa
Serosa/Adventitia

Question 2

What comprise the mucosa layer?

Answer 2

Epithelium- interacts w content of alimentary canal
Lamina propria
Muscularis mucosae made of only smooth muscle separates mucosa and submucosa

Question 3

What comprise the submucosa?

Answer 3

Mainly the Meissner’s plexus

Question 4

What comprise the muscularis externa layer?

Answer 4

Contains 2 muscles layers
The inner circular layer
Outer longitudinal layer
Auerbach’s plexus is found between the 2 layers

Question 5

What is the difference between serosa and adventitia?

Answer 5

If there is a peritoneum covered is a serosa

If there is no peritoneum and just CT it is adventitia

Question 6

What are some differences found in the oral cavity?

Answer 6

No muscularis externa
No serosa/adventitia
No muscularis mucosae

Question 7

What are the characteristics of the mucosa of the oral cavity?

Answer 7

Made on non keratinized stratified squamous epithelium
Lamina propria is for support
No muscularis mucosae

Question 8

What are the characteristics of the submucosa of the oral cavity?

Answer 8

Contains minor salivary glands
Salivary glands are intrinsic glands
Secrete mucus

Question 9

What are the characteristics of the tongue?

Answer 9

Keratinized stratified squamous epithelium is found
Extrinsic and intrinsic muscles
4 different papillae: filiform, fungiform, circumvallate and foliate

Question 10

What are the characteristics of the filiform papillae?

Answer 10

Most abundant type found throughout tongue
Keratinized
No taste buds
Have a mechanical role

Question 11

What are the characteristics of the fungiform papillae?

Answer 11

Mushroom shaped
Found on anterior tongue
Taste buds located on their apical surface

Question 12

What are the characteristics of circumvallate papillae?

Answer 12

Found along anterior part of terminal sulcus
About 8-12, Large, dome-shaped
Have a moat like groove with taste buds
Have Von Ebner’s glands which produce serous (watery) secretion to flush out taste buds

Question 13

What are the characteristics of the foliate papillae?

Answer 13

Found posterolateral
Parallel ridge
Taste buds locate on their lateral surfaces

Question 14

What are the characteristics of taste buds?

Answer 14

Oval shaped
Taste pore opens into the surface
Possess sensory cells which are modified neurons
Possess support cells which are specialized fibroblasts
Located in the lingual papillae and the oral cavity especially in the glossopharyngeal arch, soft palate and epiglottis

Question 15

What are the major salivary glands?

Answer 15

Parotid-Largest, long duct and serous gland
Submandibular— Floor of the mouth, mixed gland (mostly serous)
Sublingual-Floor of the mouth, mixed gland (mostly mucous)

Question 16

What are the functions of the major salivary glands?

Answer 16

Mainly produce saliva for:
Lubrication
Moistens the food
Digestion of carbohydrates
Antimicrobial
Contains IgA
Source of calcium and phosphate

Question 17

What is the structure of the salivary glands?

Answer 17

Secretory part that can be serous, mucous or mixed
Ductal system
Stroma made of capsule, septa and adipocytes

Question 18

What are the characteristics of the serous acini?

Answer 18

Rounded, spherical
Protein secreting
Cell structure made of euchromatic nucleus, abundant RER and apical secretory granules
Stain dark (basophilic)

Question 19

What are the characteristics of the mucous acini?

Answer 19

Tubular in shape
Mucus secreting
Cell structure made of heterochromatic nucleus, frthy apperance
Pale stained

Question 20

What are the characteristics the seromucous or mixed acini?

Answer 20

Serous demi lune cap the mucus secreting acini

Question 21

What are the different types of ducts?

Answer 21

Intralobular ducts-within lobules
Interlobular ducts-between lobules made of stratified columnar epithelium
Main ducts- from glands to oral cavity

Question 22

What are the characteristics of the intralobular ducts?

Answer 22

Made of 2 types of ducts:
Intercalated ducts made of cuboidal epithelium with basally placed nucleus
Striated ducts made of columnar epithelium with centrally placed nucleus. Contain basal membrane infoldings, mitochondria, ion transport and hypotonic saliva

Question 23

What are the characteristics of the mucosa of the esophagus?

Answer 23

Epithelium is non keratinized stratified squamous epithelium
Lamina propria is made of CT and more fibrous
Muscularis mucosae different from the rest of the GI,is longitudinally oriented in bundles and made of smooth muscle

Question 24

What are the types of glands in the esophagus?

Answer 24

Mucosal glands made of esophageal cardiac glands found at the terminal and distal esophagus
Submucosal glands also called the esophageal glands proper are small and compound tubuloalveolar found in most of the esophagus

Question 25

What are the characteristics of the submucosa of the esophagus?

Answer 25

Made of dense irregular CT
Blood vessels
Nerve fibers and ganglion cells: Meissner’s plexus

Question 26

What are the characteristics the muscularis externa of the esophagus?

Answer 26

Upper part is made of skeletal muscle
Middle 1/3 made of both skeletal and smooth muscles
Lower part made of smooth muscle

Question 27

What are the characteristics of the serosa/adventitia of esophagus?

Answer 27

Esophagus has both serosa and adventitia
Adventitia is made of loose CT and is in most of the esophagus
Serosa found in the most distal portion is made of subserosal CT and contains mesothelial lining