Lecture 1: Digestive I Flashcards
(121 cards)
What are the 2 types of epithelium that line the oral cavity of the GI tract?
- Kertanized stratified squamous
- Nonkeratanized stratified squamous
Which structures in the oral cavity are lined with keratinized stratified squamous (rough surfaces) (3)?
- gingiva - gums
- hard palate = roof of the mouth
- dorsal surface of the tongue
Which structures in the oral cavity are lined with nonkeratinized stratified squamous (smooth surfaces) (3)?
- ventral surface of the tongue
- floor of the mouth
- mucosal surface of the lips and cheeks
What are papillae and where are they located on the tongue?
Mucosal elevations on the anterior, dorsal surface of the tongue
What is the shape of filiform papillae?
long thread-like shape or feather-like shaped
What is the shape of fungiform papillae?
mushroom-shaped projections
What is the shape of circumvallate papillae?
dome-shaped
Where in the oral cavity can taste buds be found? (5)?
- fungiform papillae
- circumvallate papillae
- foliate papillae
- oral mucosa
- pharyngeal mucosa
What are foliate papillae?
small lateral folds of the mucosa
groups of peaks
Which papillae is the most abundant?
filiform papillae
Which papillae is the only one that does not have taste buds?
filiform papillae
What are the 3 principal cell types of the tongue?
- neuroepithelial cells
- supporting cells
- basal cells
What are the 5 taste stimuli of the tongue?
- sweet
- salty
- bitter
- acid
- umami
Taste information reaches the cerebral cortex through which 3 nerves?
- Primarily through the facial (VII) and glossopharyngeal (IX) nerves
- Some taste information through the vagus nerve (X)
Where are sensory neurons synapse in the medulla located?
solitary nucleus
What are the functions of the oral mucosa (2)?
- forms a protective barrier → epithelium, migratory neutrophils, saliva
- resistant to entering pathogens and indigenous microbial flora
What are the protective mechanisms of the oral mucosa (4)?
- Saliva = salivary antimicrobial peptides
- Epithelium = beta-defensins expression
- Neutrophils = alpha-defensins expression
- Plasma cells = immunoglobulin A secretion into saliva (plasma cells located in the connective tissue near the secretory acini)
What are the 7 components that make up the tooth?
- Enamel
- Dentin
- Cementum (cellular and acellular)
- Periodontal ligament
- Gingiva
- Aveolar process (bone)
- Dental pulp
What 4 components make up enamel?
- amelogengin
- enamelin
- hydroxyapatite crystals
- ameloblasts
Amleoblasts are present only in developing “baby” teeth
What 3 components make up dentin?
- predentin (type I collagen, glycosaminoglycans)
- hydroxyapatite crystals
- odontoblasts
What is saliva made of (5)?
- ⍺-amylase
- lysozyme
- secretory IgA
- Water
- bicarbonate ion
“Salivating Amy Likes Intense Weed Brownies”
What are the minor salivary glands (2)? Where are they located?
- liguinal, palatine
- located in the submucosa of the oral cavity
have short ducts which empty directly to the oral cavity
What type of glands are formed when epithelial cells maintain contact with the surface of CT?
exocrine glands
What type of glands form when epithelial cells do NOT maintain contact with the surface of CT?
endocrine glands