GI system I

Question 1

What are the three types of mucosa in the oral cavity?

Answer 1

1. Masticatory mucosa2. Lining mucosa3. Specialized mucosa

Question 2

Where is the masticatory mucosa located?

Answer 2

Gingivae and hard palate

Question 3

What type of epithelium makes up the masticatory mucosa?

Answer 3

Keratinized and parakeratinized stratified squamous epithelium

Question 4

Which parts of the masticatory mucosa lack a submucosa?

Answer 4

Gingivae and palatine raphe

Question 5

What is contained in the anterior submucosa of the hard palate?

Answer 5

Adipose CT

Question 6

What is contained in the posterior submucosa of the hard palate?

Answer 6

Mucous glands

Question 7

What anchors the mucosa to the periosteum of the hard palate?

Answer 7

Collagen fibers

Question 8

What type of epithelium makes up the lining mucosa?

Answer 8

Nonkeratinized stratified squamous (parakeratinized in some areas)

Question 9

What are the layers of the lining mucosa?

Answer 9

1. Stratum basale2. Stratum spinosum3. Stratum superficiale

Question 10

What is associated with the specialized mucosa of the oral cavity?

Answer 10

Taste

Question 11

What are the four types of papillae on the dorsum of the tongue?

Answer 11

1. Filiform2. Fungiform3. Circumvallate4. Foliate

Question 12

What type of epithelium covers the filiform papillae?

Answer 12

Keratinized stratified squamous

Question 13

What is the only lingual papilla that does NOT have taste buds?

Answer 13

Filiform papillae

Question 14

What type of epithelium covers the fungiform papillae?

Answer 14

Stratified squamous epithelium, partial keratinization

Question 15

Where are the taste buds located in the circumvallate papillae?

Answer 15

In the stratified squamous epithelium

Question 16

What glands empty into the region surrounding the circumvallate papillae?

Answer 16

Lingual salivary glands (von Ebner’s glands, serous)

Question 17

What type of epithelium covers the foliate papillae?

Answer 17

Stratified squamous with taste buds

Question 18

What empties into the clefts of foliate papillae?

Answer 18

Small serous glands

Question 19

What are the three cell types of taste buds?

Answer 19

1. Neuroepithelial (sensory) cells2. Supporting cells3. Basal cells

Question 20

What are the characteristics of the neuroepithelial (sensory) cells?

Answer 20

1. Apical surface have microvilli2. Connected to neighboring cells via tight junctions3. Form synapses with CN VII, IX, or X

Question 21

What are the characteristics of the supporting cells in taste buds?

Answer 21

1. Contain microvilli and tight junctions2. Prevent cross talk between sensory cells

Question 22

What are the characteristics of the basal cells in taste buds?

Answer 22

1. Located near basal lamina 2. Serve as stem cell population

Question 23

What lies deep to the mucosa of the lip?

Answer 23

Submucosa which houses labial salivary glands

Question 24

What kind of secretory cells make up the parotid gland?

Answer 24

Only serous

Question 25

What kind of secretory cells make up the submandibular gland?

Answer 25

Primarily serous, some mucous

Question 26

What kind of secretory cells make up the sublingual gland?

Answer 26

Primarily mucous, some serous

Question 27

What is the acquired pellicle?

Answer 27

Protective protein coat on teeth

Question 28

What are the enzymes in saliva?

Answer 28

1. Amylase2. Lipase3. Lysozyme4. Lactoperoxidase

Question 29

What is the role of lactoferrin in saliva?

Answer 29

Antibacterial - binds iron so that bacteria cannot use it

Question 30

Which antibody is contained in saliva?

Answer 30

IgA

Question 31

What are the layers of the tooth?

Answer 31

1. Enamel - covers anatomic crown, absent at root2. Dentin - present in crown and root3. Cementum - covers root, absent at anatomic crown

Question 32

What covers the root?

Answer 32

Cementum only

Question 33

From what tissue is enamel derived?

Answer 33

Epithelial tissue

Question 34

What are the stages of tooth development?

Answer 34

1. Bud stage2. Cap stage3. Bell stage4. Amelogenesis

Question 35

What characterizes the bud stage?

Answer 35

1. Invagination of oral epithelium into the mesenchyme2. Mesenchymal cells form the primordium of the dental papilla3. Cells of epithelial tooth bud secrete FGR-4 and BMP-2,4,7 to regulate shape

Question 36

What characterizes the cap stage?

Answer 36

1. Inner enamel epithelium cells differentiate into ameloblasts2. At dental papilla neural crest cells of neuroectoderm differentiate into odontoblasts3. Induced by activin BA and BMP-4 secreted by mesenchyme4. Outer enamel epithelium, stellate reticulum, and stratum intermedium start to appear

Question 37

What characterizes the bell stage?

Answer 37

1. Outer enamel epithelium2. Inner enamel epithelium3. Stratum intermedium - elaborate and transport substances to the ameloblasts4. Stellate reticulum - stellate appearing cells in an ECM of glycosaminoglycans and water

Question 38

What characterizes amelogenesis?

Answer 38

1. Process by which enamel forms2. Mamtrix production or secretory stage carried out by ameloblasts directly on previously formed dentin3. Matrix maturation is carried out by maturation stage ameloblasts - removal of organic components of partially mineralized enamel

Question 39

What characterizes maturation stage ameloblasts?

Answer 39

Ruffled borders

Question 40

What are the characteristics of cementum?

Answer 40

1. Cementoblasts actively secrete cementum 2. Avascular3. Sharpey's fibers (type I collagen) run from cementum to bone of tooth socket

Question 41

What are the characteristics of dentin?

Answer 41

1. Secreted by odontoblasts 2. Odontoblasts are derived from neural crest cells of adjacent mesenchyme3. Elongated processes of odontoblasts are embedded in dentinal tubules4. Secreted throughout life

Question 42

How does the pulp cavity change with age?

Answer 42

Becomes smaller as more dentin is secreted