Mouth and swallowing

Question 1

What is the function of the hard palate?

Answer 1

To provide an ‘anvil’ against which the tongue can crush food.

Question 2

Why are the canine teeth also known as cuspids?

Answer 2

They have a single root.

Question 3

What function do the canines serve?

Answer 3

Tearing.

Question 4

What function do the incisors serve?

Answer 4

Cutting.

Question 5

What function do the premolars/molars serve?

Answer 5

Grinding.

Question 6

Describe the roles of saliva.

Answer 6

Lubrication (of mouth and food) and cleaning
-Serous fluid, mucus
Facilitation of taste
Protection against acid and bacteria
-Antibacterial enzymes (e.g. lysozyme, IgA)
-Bicarbonate
-Calcium ions
Digestion
-Salivary amylase (ptyalin), lingual lipase

Question 7

Describe the regulation of saliva production.

Answer 7

Almost entirely due to neural control
Both parasympathetic (watery) and sympathetic (mucoid) activity increase secretion
PS controlled by salivatory centre in the brain stem, driven by:
-Local stimuli (taste and touch in the mouth)
-Central stimuli (smell & sight of food, etc)
-(learned) reflex – think of Pavlov’s dogs

Question 8

Describe saliva secretion.

Answer 8

Initial isotonic fluid, containing (mainly) NaCl, protein, and/or mucus

As it passes along the duct, salt reabsorption and HCO3- (and K+) secretion leads to a hypotonic, alkaline fluid.

Question 9

Name the major salivary glands.

Answer 9

Parotid
Sublingual
Submandibular

Question 10

Describe the innervation of the parotid gland.

Answer 10

Parasympathetic supply via CN IX (glossopharyngeal)

Sympathetic supply from superior cervical ganglion

Question 11

Is the parotid gland predominantly serous or mucous?

Answer 11

Serous

Question 12

What percentage volume of saliva is produced by the parotid?

Answer 12

25%

Question 13

Describe the innervation of the submandibular gland.

Answer 13

Parasympathetic supply via CN VII (facial)

Sympathetic supply from superior cervical ganglion

Question 14

Is the submandibular gland predominantly serous or mucous?

Answer 14

Mixture.

Question 15

What percentage volume of saliva is produced by the submandibular?

Answer 15

70%

Question 16

Describe the innervation of the sublingual gland.

Answer 16

Parasympathetic supply via CN VII (facial)

Sympathetic supply from superior cervical ganglion

Question 17

Is the sublingual gland predominantly serous or mucous?

Answer 17

Mucous.

Question 18

What percentage volume of saliva is produced by the sublingual?

Answer 18

5%

Question 19

Which salivary gland is the predominant producer of amylase and proline-rich proteins?

Answer 19

Parotid?

Question 20

Which salivary gland is the predominant producer of lysozyme and lactoperoxidase.

Answer 20

Submandibular.

Question 21

Which salivary gland is the predominant producer of lingual lipase?

Answer 21

Sublingual.

Question 22

What kind of linkages make up starch?

Answer 22

α-1,4 and α-1,6

Question 23

At which site can α-amylase cut?

Answer 23

α-amylases can only cut at α-1,4 sites, and not adjacent to the α-1,6 sites

Question 24

How does lingual lipase work?

Answer 24

Cleave the outer fatty acids off triglycerides, leaving diacyl glycerol.

Question 25

Name the ion channel-based taste receptors.

Answer 25

Salty and sour.

Question 26

Name the GPCR-based taste receptors.

Answer 26

Sweet, bitter and umami.

Question 27

What is the cephalic phase?

Answer 27

The cephalic phase of gastric secretion occurs even before food enters the stomach, especially while it is being eaten. It results from the sight, smell, thought, or taste of food, and the greater the appetite, the more intense is the stimulation. Neurogenic signals that cause the cephalic phase of gastric secretion originate from the cerebral cortex and in the appetite centers of the amygdala and hypothalamus.They are transmitted through the dorsal motor nuclei of the vagi and then through the vagus nerve to the stomach. This phase of secretion normally accounts for about 20 percent of the gastric secretion associated with eating a meal.