Anatomy of Upper GI Flashcards
What makes up the Upper GI tract
mouth/ oral region
pharynx
oesophagus
stomach
duodenum
what is the function of swallowing
move food from oral cavity to stomach
clear naso/oropharynx
preotect upper resp tract
types of swallowing
voluntary- conciously, caused by susbstance in mouth and cerebral cortex
spontaneous- unconciously, no cortical influence
3 phases of swallowing
oral
pharengeal
oesophageal
oral phase
forms food bolus (round, smooth, lubricated, broken down food)
involves salivary gland, teeth, muscles of tounge/ mastication, soft palate and facial muscles
2 parts of oral phase
preparatory- voluntary, produces food bolus, varied time, elevated tounge, soft palate closes pharynx
transit- moves bolus towards pharynx, soft palate elevated to stop inspiration, activates swallowing reflex
salivary glands
3 types- sublingual, submandibular, parotid gland
produces saliva
exocrine glands
saliva breaks down food, produces bolus, helps taste and protects oral cavity
mastication (chewing)
process of grinding down food
important to produce bolus
jaws move teeth which crushes food and facial muscles move food towards teeth
muscles of mastication
lateral pterygoid moves mandible down
temporalis, masseter and medial pterygoid move mandible up
all causes teeth to crush food
functions of teeth
incisors- cuuting and shearing
canines- gripping and tearing
premolars- tearing and crushing
molars - chewing, crushing and grinding
pharengeal phase
involuntary, 0.6s, inspiration inhibited
food bolus pushed to oropharynx
epiglottis and closed vocal chords close larynx which pushes food into laryngeophraynx
the food bolus pushed towards upper oesophageal sphincter which opens
muscles of pharynx
elevators of pharynx - salpingopharyngeus, palatopharyngeus, stylopharyngeus
constrictor muscles- superior, middle, inferior
oesophageal phase
moves food bolus into oesophagus
upper oesopheal sphinctor opens due to relaxation of inferior constrictor muscles, pressure of food bolus and suprahyoid muscles contraction
Oesophagus
thick muscular tube
C6 to T10