process of acquiring nutrition
alimentation
what are the stages of alimentation
preparatory
oral
pharyngeal
esophageal
what are the voluntary stages of alimentation
preparatory
oral
pharyngeal
what are the involuntary stages of alimentation
esophageal
during which stage of alimentation do we refer out to GI if there are complications
esophageal
what is the first step of the preparatory stage
ingestion
what happens during ingestion
lips seal; oro-facial muscles active
what is happening during the preparatory stage
mastication
what are the steps in mastication
- ingestion
- tongue cups, bunches in posterior, seals at alveolar ridge
- velum depresses
- salivary glands produce serous and mucous secretions
- buccinator and risorius contract (to keep mouth closed)
- tongue moves bolus to teeth or to hard palate
- mandibular muscles alternate to chew
what is a bolus
masticated food
what motion do we use to chew
rotary
what are the salivary glands
parotid, submandibular, sublingual
what is happening in the oral stage of alimentation
propulsion of the bolus
what are the steps of the propulsion of the bolus
- tongue dorsum depresses and retracts
- front of tongue body elevates to hard palate
- bolus reaches faucial pillars, velum, and tongue dorsum
what is the trigger point in alimentation
tongue dorsum
what is happening in the pharyngeal stage of alimentation
deglutition (swallowing)
at what stage of alimentation do you stop breathing
pharyngeal
what are the steps of deglutition
- respiration stops
- velum elevates
- vocal folds adduct
- epiglottis descends - larynx rises and advances
- cricopharyngeus relaxes
- posterior faucial pillars (palatopharyngeus) move medially
- upper, middle, and inferior pharyngeal muscles contract in sequence
- bolus splits at epiglottis and passes through the pyriform to the esophageal opening
what is happening during the esophageal stage
transit
what are the steps of transit
- bolus passes the upper esophageal sphincter and the cricopharyngeus contracts
- respiration resumes
- bolus travels through the esophagus by peristaltic motion of the smooth muscles
- bolus reaches the lower esophageal constrictor
what are the sensory stimuli in alimentation
gustatory
olfactory
tactile
- taste
- sweet, salty, umami stimulate salivation, tongue protrusion, release of insulin
- bitter and sour stimulate gagging, coughing, excess salivation
gustatory
- pleasant odors stimulate emotion, memory, salivation
- noxious odors stimulate gagging and vomiting
olfactory
- pressure
- heat
- pain
tactile
