oral cavity and upper GI tract

Question 1

stages of swallowing after mastication

Answer 1

lift and retract tongue -> bolus into oropharynx -> close of nasopharynx -> raise larynx anteriorly -> peristaltic wave of constrictor muscles -> relax cricopharyngeas, open oesophagus

Question 2

what muscles lifts and retracts the tongue

Answer 2

styloglossus (from styloid process), intrinsic muscles of tongue

Question 3

what muscle contracts to move the bolus into oropharynx

Answer 3

palatoglossus

Question 4

how is the nasopharynx closed off to prevent food entering the nasal cavity

Answer 4

soft palate is raised by levator muscles

Question 5

effect of raising larynx anteriorly when swallowing

Answer 5

closed off by epiglottis, so food can’t enter airway