GI anatomy I Flashcards
what is the oral cavity made up of?
mouth, tongue, teeth, palate, palatine tonsils
what is the oral vestibule and the oral cavity proper?
oral vestibule = slit-like space between teeth and lips
oral cavity proper = space between upper and lower dental arches ; where tongue lays at rest
what muscles keep food between upper/lower teeth?
buccinator and obicularis iris
-labial frenula = free-edged mucosal folds at midline of lips
where are the cheeks formed over? why is cheek fat prominent in babies?
over zygomatic bones and processes
-buccal fat more prominent in babies to prevent collapsing cheeks from sucking motion
what are cheek dimples?
-genetic ‘flaw’
-2 bundles of zygomaticus major muscle instead of one
-fovea buccalis
what are the gums covered with and attached to?
-fibrous tissue covered with mucus membrane
-gingivae proper attached to alveolar processes (mandible, maxillae, dental)
-excellent blood supply/innervation
what are teeth?
hard conical structures set within alveoli of upper and lower jaws
how many teeth do children have? adults?
children have 20 primary teeth
adults normally have 32 secondary (permanent teeth)
what is the arrangement of secondary teeth in adults?
from back to front:
-molars (3)
-premolars (2)
-canine (1)
-lateral incisor (1)
-medial incisor (1)`
what are the parts of a tooth?
-crown, neck, root
what are teeth composed of?
-dentin covered by enamel over crown
-cement over root
what is the function of the pulp cavity and the root canal?
pulp cavity = connective tissue, vessels, nerves (CN V)
root canal transmits nerve and vessels
what is the tongue involved in? innervation?
-mastication, taste, deglutition, articulation, oral cleansing
-innervated by CN XII (motor; hypoglossal nerve)
where is the root and body of the tongue?
-root is posterior third
-rest is visible and most motile (body)
what do the surfaces of the tongue have?
dorsum (top) and lateral surfaces have papillae (taste buds)
-follate
-vallate
-fungiform
-filiform
what are some genetic variation in taste buds?
-PTC “super tasters”
-sodium benzoate
what are the three salivary glands?
-parotid
-submandibular
-sublingual
what are the functions of the salivary glands?
-moisten mucus membrane of mouth
-lubricate food
-digest starches
- “mouthwash”
-prevent tooth decay
where does the esophagus extend to and terminate at?
-from pharynx to stomach
-terminates by entering stomach
-passes though esophageal hiatus (at level T10)
how expandable is the stomach?
-2-3 L of food
-reservoir and mixer for enzymatic digestion
what is the gastric mucosa?
- smooth inner surface that contracts to form rugae (fold)
what are the functions of rugae?
-increase surface area for digestion
-provide elasticity for stomach expansion
what is the widest part of the small intestine?
duodenum (~25 cm long)
-majority of digestion and nutrient absorption
what does the duodenum recieve?
-chyme (stomach)
-bile (bile duct)
-pancratic fluid (via pancreatic duct)
what is a cholecystectomy?
removal of the gallbladder
-minimal changes to digestive tract
what are the effects of exocrine pancreatic insufficiency?
maldigestion and malabsorption
-fatigue, anemia, vitamin D deficiency, steatorrhea, abdominal distention
where does the pancreas lie?
retroperitoneally
posterior to stomach
-superior to L/R renal arteries and veins
what are the functions of the pancreas?
-produce pancreatic juices (alkaline to reduce acidity; digestion)
-glucagon production (turns glycogen–>glucose)
-enzyme production
-produce insulin (glucose–> muscle cells)
