Swallowing

Question 1

How is swallowing initiated?

Answer 1

When pressure receptors in the walls of the pharynx are stimulated by food or drink, forced into the rear of the mouth by the tongue

Question 2

What are the 3 continuous segments of the pharynx shared between the gastro-intestinal and respiratory tracts?

Answer 2

Nasopharynx
Oropharynx
Laryngopharynx

Question 3

What nerves with nasopharynx?

Answer 3

Maxillary nerve (V2- second bean chi of trigeminal nerve(V) )

Question 4

What nerve oropharynx ?

Answer 4

Glossopharyngeal nerve (IX)

Question 5

Laryngopharynx nerve?

Answer 5

Vagus Nerve (X)

Question 6

Explain stage 1 swallowing !!

Answer 6

Voluntary;
Food compresses against roof of mouth and pushed towards oropharynx by the tongue.
The buccinator and suprahyoid muscles manipulate food during chewing and also elevate the hyoid bone and flatten the floor of the mouth.

Question 7

Explain stage 2 of swallowing ?

Answer 7

Involuntary:
Nasopharynx closed off by soft palate - via action of muscles of the palate which tense and elevate it forming food bolus.
Pharynx is shortened and widened by elevation of hyoid bone - via action of muscles of the palate floor which depress the mandible if the hyoid bone is fixed or elevate the hyoid bone and larynx if the mandible is fixed.