Pharynx -additional to slide 9 and 10- gag reflex

Question 1

What is the pharynx?

Answer 1

Space that connects the nose and mouth above to the larynx and oesophagus below involved in breaching, speech,coughing etc

Question 2

What does it protect against?

Answer 2

Inhalation of solids / liquids into lungs

Fragments of teeth, amalgam material, dental tools, orthodontic appliances

Question 3

what 3 areas of the pharynx are there?

Answer 3

• nasopharynx
• oropharynx
• larngopharynx

Question 4

what makes up the respiratory tract?

Answer 4

nasal cavity
oral cavity
larynx
trachea

Question 5

what makes up the alimentary tract?

Answer 5

oral cavity

oesophagus

Question 6

what are the layers from left to right from the pharynx to the vertebrae?

Answer 6

• pharynx
• pharyngeal muscle
• buccopharnygeal fascia
• retropharyngeal space
• alar fascia
• retropharyngeal space
• prevertebral fascia
• prevertebral muscle
• longitudinal ligament

Question 7

what 2 types of muscles are found in the pharynx?

Answer 7

circular

longitudinal

Question 8

what areas of the circular muscles are there?

Answer 8

• superior
• middle
• inferior

Question 9

how do the 3 areas of the circular muscles move food down?

Answer 9

-contract sequentially

Question 10

what nerve innervates the circular muscles?

Answer 10

Innervated by CN X - pharyngeal plexus

Question 11

where do the circular muscles insert?

Answer 11

midline raphe

Question 12

where does the superior circular muscles attach from the midline raphe to?

Answer 12

• pterygoid hamulus
• pterygomandibular raphe
• mylohyoid line

Question 13

where does the middle circular muscles attach from the midline raphe to?

Answer 13

greater horn of hyoid

Question 14

where does the inferior circular muscles attach from the midline raphe to?

Answer 14

• thyroid cartilage (oblique line)

- cricoid cartilage

Question 15

what is the space between superior and middle circular muscles?

Answer 15

gateway to the mouth

Question 16

what is found in the gateway to the mouth?

Answer 16

• CN IX
• Lingual artery
• Stylopharyngeus muscle

Question 17

what are the 3 longitudinal muscles?

Answer 17

• stylopharyngues
• palatopharyngeus
• saplingopharyngeus

Question 18

what route does the stylopharyngess take?

Answer 18

from the styloid process and passes through ‘gateway to the mouth’ with the glossopharyngeal nerve

Question 19

what is the only muscle supplied by the CN IX?

Answer 19

stylopharyngeus

Question 20

where do all 3 longitudinal muscles insert?

Answer 20

posterior border of thyroid cartilage

Question 21

what action does the longitudinal muscles do?

Answer 21

elevate pharynx and larynx

Question 22

what muscles does the CN X supply?

Answer 22

• palatopharyngeus

- salpingopharyngeus

Question 23

what muscles does the CN IX supply?

Answer 23

stylopharyngeus

Question 24

What makes up the pharyngeal plexus?

Answer 24

nerve fibres derived from CN IX and CN X, sympathetic axons (from sympathetic trunk) and parasympathetic axons

Question 25

what is the motor supply to the pharynx?

Answer 25

``` all supplied by CN X via pharyngeal plexus except stylopharyngeus (CN IX) ```

Question 26

what is the sensory supply to the pharynx?

Answer 26

Mucosa is mainly supplied by: - CN IX - CN V2 in parts of nasopharynx - CN X in parts of laryngopharynx

Question 27

what is the sensory nerve supply to the nasopharynx?

Answer 27

- CN V2 – just anterior and superior to auditory tube | - CN IX

Question 28

what is the sensory nerve supply to the oropharynx?

Answer 28

-CN IX | includes tonsillar fossa and posterior tongue

Question 29

what is the sensory nerve supply to the laryngopharynx?

Answer 29

- CN IX – just superior to epiglottis | - CN X

Question 30

what is a gag reflex?

Answer 30

protective reflex

Question 31

what happens during a gag reflex?

Answer 31

Stimulates sensory nerve fibres of CN IX: - posterior 1/3 of tongue - tonsils - walls of oropharynx (also nasopharynx and auditory tube/middle ear) - Tries to close off oropharynx

Question 32

what muscles are involved in a gag reflex?

Answer 32

- constrictors of pharynx (CN X) - longitudinal muscles of pharynx (CN IX and X) - tongue and soft palate

Question 33

what are the 4 steps of swallowing?

Answer 33

1) Food bolus squeezed to back of mouth and tongue against palate 2) Nasopharynx closed off, Larynx elevated,Pharynx enlarged to receive bolus 3) Pharyngeal constrictors contract sequentially, Epiglottis deflects bolus 4) Bolus moves into oesophagus