GI-Salivary Secretions

Question 1

What is the primary control of the secretion of the salivary glands?

Answer 1

PSNS

Question 2

What enzyme of saliva initiates the digestion of carbs?

Answer 2

a-amylase

Question 3

What kind of bonds does a-amylase cleave?

Answer 3

internal a-1,4-glycosidic bonds

Question 4

What enzyme of salivary secretions begins the digestion of triglycerides?

Answer 4

Lingual Lipase

Question 5

What is released by the salivary gland with the function of binding to Vitamin B12 (cobalamin) in the acid environment of the stomach?

Answer 5

Haptocorrin

Question 6

What is secreted in the saliva as an immunological response against bacteria and viruses?

Answer 6

IgA

Question 7

What is secreted in the saliva to chelate iron?

Answer 7

Lactoferrin

Question 8

What is the largest of the salivary glands?

Answer 8

Parotid

Question 9

What cells make up the Parotid gland and what do they produce large amounts of?

Answer 9

Serous cells; H2O, HCO3-, and enzymes

Question 10

What percentage of the total volume of saliva does the Parotid gland produce at rest flow?

Answer 10

25%

Question 11

What percentage of the total volume of saliva does the Parotid gland produce when stimulated?

Answer 11

80%

Question 12

What kind of gland is the Submandibular gland considered, based on the type of fluid produced?

Answer 12

Mixed; mucus and serous

Question 13

What is the major component of the Submandibular gland, that when at rest accounts for the largest component of salivary volume (~70%)

Answer 13

Mucus

Question 14

What kind of gland is the Sublingual gland considered, based on the type of fluid produced?

Answer 14

Primarily mucus, with a small serous component

Question 15

Where can smaller salivary glands be found?

Answer 15

tongue, lips, and palate

Question 16

The Acinus of the salivary secretory unit is the round portion that is surround by Acinar Cell that produce …

Answer 16

the saliva and mucus

Question 17

What surrounds the Acinar Cells that can aid in the expulsion of freshly secreted saliva out of the Acinus and into the Intercalated and Striated Duct Regions?

Answer 17

Myoepithelial cells

Question 18

The efferent impulses of the PSNS are distributed by what two nerves and mediated by what respective receptors?

Answer 18

Facial VII (muscarinic) and Glossopharyngeal IX (cholinergic)

Question 19

The SNS also stimulates the production of saliva, with its effects mediated through what receptors?

Answer 19

B-adrenergic receptors

Question 20

Higher Sympathetic outflow (during low PSNS stim.) stimulates … secretions, while also stimulating vaso-constiction thus reducing the … secretions.

Answer 20

mucus; serous

Question 21

Conditioned stimuli, smell, taste, chewing, and nausea stimulate … in the Medulla Oblongata?

Answer 21

Nuclei Salvatorii

Question 22

In the PSNS stimulation through CN VII and IX, what NT is released?

Answer 22

ACh

Question 23

ACh stimulates the salivary gland to increase its level of … that leads to an increase in cell Ca2+.

Answer 23

IP3

Question 24

The increased cell Ca2+ in the salivary gland stimulates what 5 things?

Answer 24

vasodilation, increased metabolism, myoepithelial cell contraction, increased secretion, and cell growth

Question 25

The higher stimuli trigger a Sympathetic Mediated response through the Thoracic Spinal Nerves, releasing ....(NT) to ....

Answer 25

ACh --> Superior Cervical Ganglion

Question 26

What NT does the SCG release?

Answer 26

NE

Question 27

What does NE increase in the salivary gland cell, that leads to an increase cell Ca2+?

Answer 27

cAMP

Question 28

What is another salivary gland regulatory mechanism that is released by the postganglionic fiber?

Answer 28

VIP (vasoactive intestinal peptide)

Question 29

What does VIP mediate?

Answer 29

vasodilation by increasing BF and volume secretion

Question 30

[K+] is higher in ...

Answer 30

saliva

Question 31

Salivary Na+ and Cl- ... than plasma.

Answer 31

less

Question 32

Salivary HCO3- is ... than plasma except at LOW flow rates.

Answer 32

greater

Question 33

The ionic gradients of the Acinar Cells are set up by a basolateral ...

Answer 33

Na/K-ATPase

Question 34

Na+ cycles inward in the Acinar Cell down the concentration gradient by cotransport with ...

Answer 34

Cl-

Question 35

K+ diffuses out of the Acinar Cell down its electrochemical gradient, along with ... across what membrane?

Answer 35

HCO3-; apical

Question 36

As the salivary secretion does past the Duct Cells what is reabsorbed?

Answer 36

Na+ and Cl-

Question 37

As the salivary secretion does past the Duct Cells what is secreted?

Answer 37

smaller amount of K+ and HCO3-

Question 38

The salivary ductal solution is ... due to its impermeability to water.

Answer 38

hypotonic

Question 39

As flow past the Salivary Duct Cells increases, [Na+] and [Cl-] in the salivary lumen ...

Answer 39

increase

Question 40

As flow past the Salivary Duct Cells increases, [K+] in the salivary lumen ...

Answer 40

decreases slightly

Question 41

As flow past the Salivary Duct Cells increases, [HCO3-] in the salivary lumen ...

Answer 41

increases because its secretion is increased by the same stimuli that increases the flow rate

Question 42

Salivary flow rate has what affect on pH?

Answer 42

increases because of the increase in HCO3-