Digestive System: Oral cavity/mucosa, Tongue, Teeth, Salivary glands

Question 1

What are the functions of the digestive system?

Answer 1

Ingestion, mastication, secretion, absorption, elimination of wastes, motility, hormone release, chemical digestion

Question 2

What makes up the oral cavity?

Answer 2

Tongue, teeth, minor and major salivary glands, tonsils, lips

Question 3

What are the 3 types of oral mucosa?

Answer 3

Masticatory mucosa, lining mucosa, specialized mucosa

Question 4

Where is the masticatory mucosa found?

Answer 4

Gingiva and hard palate

Question 5

What type of surface epithelium makes up the masticatory mucosa?

Answer 5

Keratinized or parakeratinized stratified squamous epithelium (superficial cells of parakeratinized stratified squamous cells keep their nuclei)

Question 6

What are the 2 parts of the lamina propria of the masticatory mucosa?

Answer 6

Papillary layer- thick loose CT, has blood vessels, nerves, sensory receptors, some Meissner’s corpuscles
Reticular layer- more dense ct

Question 7

Where is the lining mucosa of the oral mucosa found?

Answer 7

Soft palate, underside of tongue, floor of mouth, cheeks, lips

Question 8

What makes up the surface epithelium of the lining mucosa?

Answer 8

Generally nonkeratinized stratified squamous
Occasionally parakeratinized stratified squamous
Keratinized stratified squamous (lips, vermillion border)

Question 9

What areas of stratified squamous is thicker than the areas of keratinized stratified squamous?

Answer 9

Nonkeratinized

Question 10

What makes up the lamina propria of the lining mucosa?

Answer 10

Loose ct with blood vessels and nerves

Question 11

What makes up the submucosa of the lining mucosa?

Answer 11

More dense ct (found in most places, can have minor salivary glands, sebaceous glands, larger blood vessels and nerves)

Question 12

Where is the specialized mucosa of the oral cavity found?

Answer 12

Dorsal surface of tongue

Question 13

What makes up the surface epithelium of specialized mucosa?

Answer 13

Keratinized stratified squamous on filiform papilla

Stratified squamous on all other papillae

Question 14

What are the general functions of the specialized mucosa?

Answer 14

Move food and taste

Question 15

How is the mucosa of the tongue?

Answer 15

Thicker dorsally, thinner and smoother posteriorly

Question 16

What surface epithelium makes up the tongue?

Answer 16

Specialized, includes papillae: filiform, fungiform, foliate, vallate (circumvallate)

Question 17

What glands are associated with vallate papilla and what is their function?

Answer 17

Small salivary glands (von Ebner), they function to produce serous fluid to cleanse the taste buds on these papillae

Question 18

Which papillae are taste buds NOT included on?

Answer 18

Filliform papillae

Question 19

What makes up the lamina propria of the tongue?

Answer 19

Loose ct; adipose possible

Question 20

What makes up the submucosa of the tongue?

Answer 20

Considered present on tongue but adipose is possible

Question 21

What is unique about the submucosa of the tongue?

Answer 21

Contains lingual salivary glands that produce same products as the major salivary glands

Question 22

What are the intrinsic tongue muscles and how are they arranged?

Answer 22

Superior longitudinal muscle, Vertical muscles alternating with Transverse muscles, Inferior longitudinal muscle
*arranged from dorsal to posterior within the tongue(?)

Question 23

What is the function of the intrinsic tongue muscles?

Answer 23

Change shape of tongue (important for phonation and moving food around)

Question 24

What are the layers of the teeth from outside to inside?

Answer 24

Ameloblasts, enamel, dentin, predentin, odontoblast, dental papilla

Question 25

What are the ameloblasts made up of and what and what's their function?

Answer 25

Polarized columnar cells They produce enamel *ameloblasts lost following tooth eruption

Question 26

What is unique about enamel and what is it made of?

Answer 26

2mm thick, it is the hardest substance in the body | Made of interlinked enamel rods

Question 27

Can enamel be made after tooth eruption?

Answer 27

No

Question 28

What is unique about dentin and what does it contain?

Answer 28

It is harder than bone | Contains thin dentinal tubules containing nerves and cell processes of odontoblasts

Question 29

What is the precursor to dentin before mineralization?

Answer 29

Predentin

Question 30

What makes up odonotoblasts and what's their function?

Answer 30

Columnar cells lining pulp cavity | They repair and produce dentin (maintain dentin)

Question 31

What makes odontoblasts so different from ameloblasts?

Answer 31

Odontoblasts survive in adults unlike ameloblasts

Question 32

What is dental papilla/dental pulp made of and what is a potential problem?

Answer 32

CT with many blood vessels and nerves | Excessive inflammation can be a problem

Question 33

What are the three salivary glands?

Answer 33

Parotid, Submandibular, Sublingual

Question 34

What is unique about the parotid gland?

Answer 34

It is the largest salivary gland and produces ~30% of total salivary output; also it is 100% serous producing

Question 35

What is the parotid gland most affected by?

Answer 35

Mumps-- facial nerve passes through

Question 36

What happens to the parotid gland as one ages?

Answer 36

It becomes infiltrated with adipose

Question 37

What are the products secreted by the parotid gland?

Answer 37

Salivary amylase (alpha amylase--> breaks down carbs) Lysosome Secretory IgA

Question 38

Is the submandibular gland smaller than the parotid?

Answer 38

Yes

Question 39

Can the submandibular gland become fatty?

Answer 39

Yes, infiltration possible by midlife

Question 40

Is the submandibular gland 100% serous producing?

Answer 40

No, it is a mixed gland producing mucus AND serous products; ~80-90% serous producing

Question 41

What is unique about the submandibular gland?

Answer 41

It has serous demilunes

Question 42

Is the sublingual gland the smallest salivary gland? How much salivary output does it contribute to?

Answer 42

Yes it is the smallest salivary gland, ~5% of total salivary output

Question 43

Is the sublingual gland mixed?

Answer 43

Yes, it produces mucus AND serous products; ~8% mucus producing

Question 44

Where do all of the serous producrs of the sublingual gland come from?

Answer 44

Serous demilunes; no separate serous acini

Question 45

What are the functions of the saliva?

Answer 45

Lubricating and cleansing for the oral cavity Antibacterial activity Dissolves food materials for taste sensation Initiates digestion: salivary amylase/lipase Aids swallowing by moistening food, helps form bolus Wound healing due to clotting factors, epidermal growth factor present

Question 46

What is saliva secretion stimulated by?

Answer 46

Autonomic efferent impulses

Question 47

What will parasympathetic impulses do to saliva secretion?

Answer 47

Increases amount of watery secretion

Question 48

What will sympathetic impulses do to saliva secretion?

Answer 48

Result in a decreased amount of saliva with a thicker consistency--> dryer oral cavity

Question 49

What does the mucosa of the luminal wall include?

Answer 49

Surface epithelium, lamina propria (loose ct), muscularis mucosae (smooth muscle)

Question 50

What does the submucosa of the luminal wall include?

Answer 50

More dense CT, larger blood vessels, submucosal (Meissner's) plexus which influences mucosa

Question 51

What plexus is found in the muscularis externa of the luminal wall, where is it found, and what is its function?

Answer 51

Myenteric (Auerbach) plexus Found between circular and longitudinal muscle layers Function is to influence muscularis externa

Question 52

What type of muscle is the muscularis externa and how is its orientation?

Answer 52

Smooth muscle | Orientation: inner circular, outer longitudinal (normal)

Question 53

Where is the serosa/adventitia found in the luminal wall?

Answer 53

Next to the muscularis externa

Question 54

What is serosa in the luminal wall?

Answer 54

Edge of simple squamous epithelium (can contain CT), it is serous producing

Question 55

What is adventitia in the luminal wall?

Answer 55

CT, seen in vertical organs