Flashcards in GI system I Deck (42):
What are the three types of mucosa in the oral cavity?
1. Masticatory mucosa2. Lining mucosa3. Specialized mucosa
Where is the masticatory mucosa located?
Gingivae and hard palate
What type of epithelium makes up the masticatory mucosa?
Keratinized and parakeratinized stratified squamous epithelium
Which parts of the masticatory mucosa lack a submucosa?
Gingivae and palatine raphe
What is contained in the anterior submucosa of the hard palate?
What is contained in the posterior submucosa of the hard palate?
What anchors the mucosa to the periosteum of the hard palate?
What type of epithelium makes up the lining mucosa?
Nonkeratinized stratified squamous (parakeratinized in some areas)
What are the layers of the lining mucosa?
1. Stratum basale2. Stratum spinosum3. Stratum superficiale
What is associated with the specialized mucosa of the oral cavity?
What are the four types of papillae on the dorsum of the tongue?
1. Filiform2. Fungiform3. Circumvallate4. Foliate
What type of epithelium covers the filiform papillae?
Keratinized stratified squamous
What is the only lingual papilla that does NOT have taste buds?
What type of epithelium covers the fungiform papillae?
Stratified squamous epithelium, partial keratinization
Where are the taste buds located in the circumvallate papillae?
In the stratified squamous epithelium
What glands empty into the region surrounding the circumvallate papillae?
Lingual salivary glands (von Ebner's glands, serous)
What type of epithelium covers the foliate papillae?
Stratified squamous with taste buds
What empties into the clefts of foliate papillae?
Small serous glands
What are the three cell types of taste buds?
1. Neuroepithelial (sensory) cells2. Supporting cells3. Basal cells
What are the characteristics of the neuroepithelial (sensory) cells?
1. Apical surface have microvilli2. Connected to neighboring cells via tight junctions3. Form synapses with CN VII, IX, or X
What are the characteristics of the supporting cells in taste buds?
1. Contain microvilli and tight junctions2. Prevent cross talk between sensory cells
What are the characteristics of the basal cells in taste buds?
1. Located near basal lamina 2. Serve as stem cell population
What lies deep to the mucosa of the lip?
Submucosa which houses labial salivary glands
What kind of secretory cells make up the parotid gland?
What kind of secretory cells make up the submandibular gland?
Primarily serous, some mucous
What kind of secretory cells make up the sublingual gland?
Primarily mucous, some serous
What is the acquired pellicle?
Protective protein coat on teeth
What are the enzymes in saliva?
1. Amylase2. Lipase3. Lysozyme4. Lactoperoxidase
What is the role of lactoferrin in saliva?
Antibacterial - binds iron so that bacteria cannot use it
Which antibody is contained in saliva?
What are the layers of the tooth?
1. Enamel - covers anatomic crown, absent at root2. Dentin - present in crown and root3. Cementum - covers root, absent at anatomic crown
What covers the root?
From what tissue is enamel derived?
What are the stages of tooth development?
1. Bud stage2. Cap stage3. Bell stage4. Amelogenesis
What characterizes the bud stage?
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
What characterizes the cap stage?
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
What characterizes the bell stage?
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
What characterizes amelogenesis?
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
What characterizes maturation stage ameloblasts?
What are the characteristics of cementum?
1. Cementoblasts actively secrete cementum 2. Avascular3. Sharpey's fibers (type I collagen) run from cementum to bone of tooth socket
What are the characteristics of dentin?
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