GIT —-> Deglutition (swallowing)

Question 1

What are the oral phases ?

Answer 1

1- Oral cavity boundaries
2- Mastication process
3- Salivating
4- Downward slope of tongue

Question 2

What are the mandibular depressors (open the jaw) muscles ?

Answer 2

• Lateral pterygoid
• Digastric anterior belly
• Mylohyoid
• Geniohyoid

Question 3

What are the mandibular elevators muscles ?

Answer 3

• Masseter muscle
• Temporalis
• Medial pterygoid

Question 4

The mandibular muscles are innervated by what nerve ?

Answer 4

All of the mandibular muscles are innervated by the trigerminal nerve, which is cranial nerve 5, third division.

Question 5

The elevation of the tongue is carried out by?

Answer 5

• Extrinsic tongue muscles.

Question 6

What is central trough formed by?

Answer 6

• Intrinsic muscles of the tongue.

Question 7

Whats the whole purpose of elevating the tongue and forming a central trough?

Answer 7

• To create a downward slope.

Question 8

By what nerve the extrinsic and intrinsic muscles of tongue are innervated ?

Answer 8

• Cranial nerve 12 (hypoglossal nerve)

Question 9

Mention the pharyngeal phase ?

Answer 9

1- Prevent bolus from going into nasopharynx.
2- Prevent bolus from going into larynx.
3- Ensure bolus enters pharynx.
4- Upper esophageal sphincter (UES) relaxes.

Question 10

Mention esophageal phase ?

Answer 10

• Primary peristalsis is continuous of pharyngeal peristalsis
• Secondary peristalsis (local reflex) if bolus is stuck