Theme 5: Rest & Digest (GI/Met)

Question 1

What are the boundaries of the nasopharynx?

Answer 1

Extends to the uvula of the soft palate.

Question 2

What are the boundaries of the oropharynx?

Answer 2

Extends from the uvula (the end of the palate) down to the level of the hyoid bone.

Question 3

What are the boundaries of the laryngopharynx?

Answer 3

Extends from the level of the hyoid bone to the

Question 4

What are the muscles of mastication and which nerve innervates them?

Answer 4

Masseters, temporalis and the medial and lateral pterygoids. Supplied by the mandibular divison of the trigeminal nerve (CN V).

Question 5

Which of the muscles of mastication are involved in elevating the mandible?

Answer 5

Masseters, temporalis and the medial pterygoids.

Question 6

Which of the muscles of mastication are involved in lateral movements of the mandible?

Answer 6

Lateral pterygoids.

Question 7

Which of the pharyngeal arches do the muscles of mastication arise from?

Answer 7

First pharyngeal arch.

Question 8

Which of the muscles of mastication are involved in protracting and retracting the mandible?

Answer 8

Lateral pterygoids and temporalis respectively.

Question 9

What is the function of the epiglottis?

Answer 9

It is a flap of tissue located in the oropharynx that covers the opening of the trachea during swallowing, preventing aspiration.

Question 10

What is xerostomia and what can happen as a result of it?

Answer 10

A disorder of insufficient saliva production. Food can still be eaten provided it is moist enough. However, teeth and mucosa will degrade quickly (mucosa will dry out, teeh will not be washed and oral environment will become less alkaline).

Question 11

What are the three pairs of salivary glands known as and what type of saliva do they secrete (mucus-rich or serous?)? Order them in volume of secretions.

Answer 11

Sub-mandibular (70%) - Mixed
Parotid (25%) - Serous
Sub-lingual (5%) - Mucus

Question 12

What are the normal constituents of saliva? What is their concentration relative to plasma?

Answer 12

Water - hypotonic
Na+, Cl- - hypotonic
Ca2+, K+, I-, HCO3- - hypertonic
Bacteriostats, mucus and amylase

Question 13

What type of glands are salivary glands? Describe their structure.

Answer 13

Exocrine glands.

Question 14

What is Sjogren’s syndrome?

Answer 14

Auto-immune destruction (by WBCs) of exocrine glands, specifically salivary and lacrimal glands. This results in xerostomia.