Saliva

Question 1

What are the 3 major exocrine salivary glands?

Answer 1

1) Parotid
2) Submandibular
3) Sublingual

Question 2

What gland produces the most secretion?

Answer 2

sub mandibular

Question 3

what gland produces the least secretion?

Answer 3

Sub lingual

Question 4

What is submandibular secretion?

Answer 4

Serous-Mucin

Question 5

What is Parotid secretion

Answer 5

Serous

Question 6

What is Sub lingual secretion?

Answer 6

Mucin

Question 7

Where is primary secretion?

Answer 7

In acini by acinar cells

Question 8

Where does secretion pass?

Answer 8

Acinus> intercalated ducts> striated ducts>excretory duct

Question 9

What is primary secreted saliva?

Answer 9

watery, inorganic ions and enzymes - similar to plasma

Question 10

how do Columnar cells modify primary to Secondary secretion?

Answer 10

in striated duct it’s modified via secretion/absorption

Question 11

What is around acini?

Answer 11

layer of smooth muscle made from myoepithelial cells

Question 12

What does smooth muscle around acini do?

Answer 12

alter flow rate to help secretion of saliva via contraction/relaxation

Question 13

Are K+ and HCO3- concs. higher in Saliva than plasma?

Answer 13

YES

Question 14

Are Na+ and Cl- concs. lower in Saliva than plasma?

Answer 14

yes

Question 15

What are reabsorbed from striated duct?

Answer 15

Na+ and Cl-

Question 16

What are secreted into lumen of striated duct?

Answer 16

K+ and HCO3-

Question 17

What does striated ductal epithelium have?

Answer 17

Low permeability to water so more ions reabsorbed

Question 18

What is secondary secretion?

Answer 18

Hypotonic

Question 19

What is primary secretion?

Answer 19

Isotonic

Question 20

What cells allow transport?

Answer 20

Columnar cell

Question 21

How do Na+ cells enter columnar cell from lumen via Apical membrane?

Answer 21

via Na+ channel and Na/H exchanger

Question 22

what is the apical membrane?

Answer 22

layer of plasma membrane towards lumen

Question 23

How does Na+ exit columnar cell via Basolateral membrane?

Answer 23

Via Na/K pump, 3 Na removed and 2K pump in

Question 24

How does Cl- enter columnar cell via apical membrane

Answer 24

via Cl/HC03- exchanger

Question 25

How does HCO3- secretion out of columnar cell occur?

Answer 25

Via apical CL/HC03- exchanger into lumen

Question 26

How does columnar cell uptake K+?

Answer 26

Na/K pump at basolateral membrane

Question 27

How does K+ secrete into lumen?

Answer 27

Apical K-H exchanger

Question 28

Evidence for 2 stage secretion ?

Answer 28

Acinar micropuncture
Poly-lysine injection- stop 2ndary reabsorp. so saliva is primary fluid now
flow rate curves

Question 29

What stimulates flow rate change?

Answer 29

Aldosterone

Question 30

What happens at low flow rates?

Answer 30

more time for secondary ductal modification

Question 31

What happens at high flow rates?

Answer 31

less time so composition reaches primary secretion

Question 32

How is Salivary secretion controlled and increased?

Answer 32

ANS- parasymp. and Sympathetic

Question 33

How does parasympathetic increase saliva secretion?

Answer 33

Acetylcholine - contract myoepithelial cells around acinus

Question 34

What does release of VIP (Vasoactive intestinal peptide) do?

Answer 34

vasodilation so inc. blood flow to Salivary glands

Question 35

What do all salivary glands have ?

Answer 35

acinar cells

Question 36

What do striated epithelium ducts have?

Answer 36

columnar cells for transport

Question 37

How does Sympathetic increase saliva secretion?

Answer 37

Adrenaline/noradrenaline- contraction of myoepithelial

Question 38

What do Na+ depleted animals have?

Answer 38

Increased Aldosterone- Na+ retention

Question 39

What stimulates ductal transport?

Answer 39

Mineralocorticoids e.g. aldosterone