Salivary and Gastric Acid Secretions Flashcards Preview

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Flashcards in Salivary and Gastric Acid Secretions Deck (56)
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1

Although not required, mastication is important for

mechanical breakdown, SA for saliva, easier swallowing

2

Saliva Function

lubrication, dissolving food for taste, heath of gums, R protein for Vit B12 absorption, amylase and ptyalin for carb digestion, HCO3 for H+ neutralization

3

3 salivary glands

parotid, submandibular, and sublingual

4

What types of cells are in salivary glands

acinar and ductal

5

Acinar cell secretions

isotonic electrolyte (Na, Cl, K, HCO3, H2O), active amylase, mucins, tight junctions permeable to water (SECRETION IS ISOTONIC)

6

Ductal cells

reabsorbs Na, HCO3 exchanges for luminal Cl, tight junctions impermeable to water

7

Which salivary gland cells have tight junctions impermeable to water?

ductal

8

Aldosterone effects salivary gland cells by

increasing the absorption of Na by ductal cells, doesn't effect rate of salivary secretion

9

What regulates rate and volume of salivary secretion?

sympathetic and parasympathetic innervation

10

Final salivary secretion is ________ in comparison to plasma. (hypo- iso- hyper- tonic)

HYPOtonic

11

PNS and SNS activity cause

INCREASED salivation, intitiated by taste, smell, tactile stimuli in mouth

12

PNS increases release of what type of saliva

watery

13

SNS increased release of what type of saliva

proteins and maintains high blood flow to gland by releasing nonadrenergic vasodilators

14

Increased rate of salivation

by PNS during nausea and vomiting

15

Decreased rate of salivation

by inhibition of PNS by fatigue, sleep, fear, dehydration

16

What electrolyte is high at all salivary flow rates

HCO3

17

At the slowest salivary flow rate...

ductal cells reabsorb most Na and exchange most Cl for HCO3, therefore Na and Cl are low, and K is high

18

At the fastest salivary flow rate...

ductal cells reabsorb little Na, therefore highest concentration of Na and lowest K

19

During maximal PNS stimulation would the Na concentration of the saliva be high or low?

HIGH, fast salivation flow rate, low Na reabsorption by ductal cells

20

Gastric secretions have 3 main functions

Digestion, modulate HCl secretion, and protect lining of gut

21

Gastric substances that aid in digestion

HCl (parietal cells), Intrinsic Factor (parietal cells), Gastric lipase (chief cells), and pepsinogen (chief cells)

22

Gastric substances that modulate HCl secretion

Gastrin (G cells), Histamine (ECL cells), Somatostatin (D cells)

23

Gastric substances that protect the stomach lining

Mucus and HCO3 (surface mucous cells and mucous neck cells)

24

Secretory cells present in cardiac glands

surface mucous cells and mucous neck cells - mucus and HCO3

25

Secretory cells present in gastric (oxyntic) glands

surface mucous cells and mucous neck cells - mucus and HCO3, parietal, chief, D cells, ECL

26

Secretory cells present in pyloric glands

surface mucous cells and mucous neck cells - mucus and HCO3, G and D cells

27

HCl secretion by parietal cells - H+ production

Carbonic Anhydrase: CO2 + H2O --> H+ + HCO3

28

HCl secretion by parietal cells - Apical Membrane

H+/K+ ATPase pump: pumps H+ into lumen and K+ into cell

29

HCl secretion by parietal cells - Basolateral membrane

Excess HCO3 is transported across in exchange for Cl-, HCO3 enters blood and CL- diffuses into lumen to generate HCl

30

HCl secretion by parietal cells - H2O

passive diffusion with HCl into lumen