23 9-10

Question 1

Identify the 3 major extrinsic salivary glands.

Answer 1

parotid, sublingual, submandibular (lie outside the oral cavity and empty their secretions into it)

Parotid and submandibular are mostly serous cells - produce a watery secretion containing ions, enzymes, small amount of mucin.

Sublingual glands contain mostly mucus cells.

(extrinsic salivary glands lie outside the oral cavity)

Question 2

Composition of saliva?

Answer 2

99.5% water, IgA, lysozyme, defensins, mucins, salivary amylase, ligual lipase.

Slightly acidic 6.75-7

1500ml per day!

Question 3

Function of saliva?

Answer 3

Cleanses the mouth

Dissolves food chemicals so they can be tasted

Moistens food and helps compact it into a bolus

Contains enzymes that begin the chemical breakdown of starchy food

Protects - IgA, lysozymes, defensin

Question 4

How is saliva regulated?

Answer 4

Primarily by parasympathetic - watery, enzyme rich saliva. Chemo and mechanoreceptors send signals to salivatory nuclei, ↑ parasympathetic via facial and glossopharangeal. Also spicy foods in the lower GI (wash away/neutralize).

Sympathetic T1-3 - thick, mucin rich saliva. Strong stimulation almost completely inhibits.

Question 5

Anatomy of the esophagus?

Answer 5

Muscular tube with all four tunics (but adventitia instead of serosa)

Mucosa is stratified squamous epithelium.

longitudinal folds when empty

secretes mucus via esophageal glands

mixture of smooth and skeletal muscle in muscularis

10” long.

gastroesophageal sphincter where it joins stomach.

Collapsed when not involved in food propulsion

Question 6

GERD

Answer 6

gastroesophageal reflux disease - burning pain that occurs when stomach acids regurgitates into the esophagus. Can happen because of excess food/drink, obesity, pregnancy, running. Also if hiatal hernia

Question 7

deglutition

Answer 7

Swallowing, involves of 22 muscles