Eat, Chew and Swallow

Question 1

where does jaw opening occur

Answer 1

at TMJ - temporomandibular joint

4 muscle responsible

Question 2

muscle responsible for opening the jaw

Answer 2

lateral pyterygoid

Question 3

muscles responsilbe for closing he jaw

Answer 3

masseter
temporalis
medial pterygoid

Question 4

nerve supplying the opening/closing of the jaw

Answer 4

mandibular division of trigeminal nerve - CN Vc (sensory and motor)

Question 5

where is TMJ located

Answer 5

at the articulation of the mandibular fossa, head of the condylar process and articular tubercle

Question 6

describe the course of CN Vc

Answer 6

from pons
through the foreman ovale
to muscles of mastication and sensory area

Question 7

3 salivary glands

Answer 7

parotid
submandibular
sublingual

Question 8

secretion of parotid gland

Answer 8

cheek aspect of upper second molar

Question 9

secretion of submandibular gland

Answer 9

base of frenulum

Question 10

secretion of sublingual gland

Answer 10

floor of the mouth

Question 11

sensation of oral cavity - superior half

Answer 11

gingiva of oral cavity and palate 
CN Vb (sensory nerve only)

Question 12

sensation of oral cavity - inferior half

Answer 12

gingiva of oral cavity and floor of mouth

CN Vc

Question 13

describe the course of CN Vb

Answer 13

from pons
through foramen rotundum
to sensory area (mid face)

Question 14

describe gag reflex of oral cavity

Answer 14

protective reflex

Question 15

sensory part of gag reflex

Answer 15

CN IX

Question 16

motor part of gag reflex

Answer 16

CN IX and CN X

Question 17

sensation of anterior tongue

Answer 17

general sensory - CN Vc

special sensory - CN VII

Question 18

sensation of posterior tongue

Answer 18

general and special sensory - CN IX

Question 19

describe the course of CNVII

Answer 19

from pontomedullary junction 
travels through temporal bone via internal acoustic meatus then stylomastoid foramen 
suplies;
anterior of tongue
muscles of facial expression 
glands in floor of mouth

Question 20

describe course of CN IX

Answer 20

from medulla
through jugular foramen
to posterior wall of oropharynx (sensory), parotid gland (secretomotor) and posterior of tongue (sensation and taste)

Question 21

extrinsic muscles of the tongue

Answer 21

4 pairs;
palatoglossus
styloglossus
hyoglossus
genionglossus

Question 22

function of extrinsic muscles of the tongue

Answer 22

change position of the tongue during mastication, swallowing and speech

Question 23

intrinsic muscles of the tongue

Answer 23

4 pairs (skeletal)
located dorsally/posteriorly

Question 24

function of intrinsic muscles of the tongue

Answer 24

modify shape of the tongue during function

Question 25

nerve supplying tongue

Answer 25

CN XII

exception of the palatoglossus

Question 26

describe course of CN XII

Answer 26

from medulla

through hypoglossal canal to extrinsic and intrinsic muscle of tongue (except palatoglossus)

Question 27

muscles of pharynx - external layer

Answer 27

circular (constrictor) muscle
overlap each other
skeletal muscle - contract sequentially
insert onto midline raphe

Question 28

nerve innervating external muscles of pharynx

Answer 28

CN X

Question 29

muscles of pharynx - intenral layer

Answer 29

longitudinal layers 
elevate pharynx and larynx;
attach to larynx
contract to shorten pharynx
raise the larynx to close over the laryngeal inlet

Question 30

nerve innervating internal muscles of pharynx

Answer 30

CN X

CN IX

Question 31

anatomy of swallowing

Answer 31

1. close lips (prevent drooling) (orbicularis oris and CN VII)
2. tongue (CN XII) pushes bolus posteriorly towards oropharynx
3. sequentially contract pharyngeal constrictor muscles (CN X) to push bolus inferiorly towards oesophagus
4. at same time, inner pharyngeal muscles (CN IX&X) contract to raise larynx, shortening pharynx and closing off the laryngeal inlet to prevent aspiration
5. bolus reaches oesophagus

Question 32

where does oesophagus begin in relation to vertebra

Answer 32

C6

Question 33

describe oesophagus

Answer 33

inferior continuation of laryngopharynx
muscular tube - collapses if empty
runs posterior to trachea and heart, anterior to vertebral bodies
terminates at cardia of stomach (immediately as it enters diaphragm)

Question 34

sphincters of oesophagus

Answer 34

anatomical upper sphincter - cricopharyngeus

physiological lower oesophageal sphincter

Question 35

nerve supply or oesophagus

Answer 35

oesophageal plexus rubs on surface to supply smooth muscle within its walls (distally);
contains parasympathetic (P) nerve fibres (vagal trunks) and sympathetic (S) nerve fibres 
these fibres influence the enteric nervous system to speed up (P) or slow down (S)

Question 36

describe how the physiological lower oesophageal sphincter is triggered

Answer 36

contraction of diaphragm
intra-abdominal pressure higher than intra-gastric pressure
oblique angle at which oesophagus enters cardiac of stomach

Question 37

function of the physiological lower oesophageal sphincter

Answer 37

reduces occurrence of reflux;

presence of a hiatus hernia will reduce its effectiveness (leading to symptoms of reflux)

Question 38

location of the physiological lower oesophageal sphincter

Answer 38

lies immediately superior to gastro-oesophageal junction;
abrupt change in type of mucosa lining the wall
Z-line

Question 39

location of the stomach

Answer 39

mainly in the left hypochondrium, epigastric and umbilical regions when the patient is supine

Question 40

structure of the stomach

Answer 40

j shaped;
cardia (anthing above cardia - fundus)
body 
rugae
pyloric antrum (pyloric sphincter)