P1 PHYSIOLOGY Flashcards
pressure receptors in the mouth inhibit what nerve
trigeminal nerve
5th Cranial nerve
trigeminal nerve
voluntary stage
oral stage
2 involuntary stages
Pharyngeal & oesophageal stages
time taken in pharyngeal stage
less than 2 seconds
time taken in oesophageal stage
8-10 seconds
what phase transports bolus to the stomach
Oesophageal phase
Inhibiting 5th cranial nerve results in
dropping of the mandible
what is chewing reflex
stretching reflex repeating itself
Importance of forming bolus of food
1- increasing surface area for chemical digestion
2- decreasing abrasion og GI lining
reaching what structure starts pharyngeal phase
when bolus touches palatoglossal arch
what areas are rich in 9th nerve ( glossopharyngeal )
palatoglossal arch
pharyngeal arch
tonsillar fossa
post. Pharyngeal wall
9th nerve activates what nerve
10th nerve ( vagus )
Activation of vagus nerve serves as
Prevention of bolus from going into nasal cavity
elevation of what structures causes block of nasopharynx
elevation of uvula & soft palate
soft palate elevation is enhanced by what nerve
5th cranial nerve ( trigeminal )
Movements preventing bolus from going into larynx
adduction of glottis
retroversion of epiglottis
larynx elevation via suprahyoid and pharynx via outer longitudinal muscles
main propulsive movement of GI
Pharyngeal peristalsis
Relaxation of what muscle causes opening of LES
cricopharyngues muscle
Contraction of which group of muscles causes elevation of pharynx & larynx
Longitudinal muscles
Contraction of which muscles propel food downward
inner circular ( pharyngeal constrictors )
Continuation of pharyngeal peristalsis termed as
Primary peristalsis
incase of failed primary peristalsis
Secondary peristalsis
Peristalsis depends on
CGRP
Acetylcholine
Somatostatin
vasointestinal peptide
thacykinin
