Saliva Production And Secretion

Question 1

Which glands secrete saliva

Answer 1

Parotid
Submandibular
Sublingual

ALL ARE PAIRS

Question 2

Where are each of the glands

Answer 2

Parotid - largest. between the back of the mouth and the ear
Submandibular - beneath floor of mouth.
Subligual -also beneath floor of mouth but more anterior than submand. smallest

Question 3

Which muscle runs between submandibular

Answer 3

Mylohyoid

Splits it into larger superficial (ontop of myohyoid) and deep lobes

Question 4

Average daily secretion

Answer 4

1-2 L

Question 5

What do the parotid glands secrete

Answer 5

Serous secretion

Question 6

What do the submandibular glands secrete

Answer 6

mixed

Question 7

What do the sublingual glands secrete

Answer 7

Only mucus

Question 8

What type of cells produces the secretions

Answer 8

Acini that line each of the glands (can be serous or mucus cells)

Question 9

What is in the serous secretion

Answer 9

Ptyalin (an a-amylase) which is an enzyme for digesting starches by hydrolysing a-1,4 bonds.
inactivated in stomach by low pH

Question 10

What is in saliva

Answer 10

Serous secretion
Lingual lipase - begins digestion of lipids, breakdown of triglyserides into fatty acids.
Mucus - contains mucin for lubrication

Question 11

2 stage process of secretion

Primary secretion

Answer 11

In acinus
Secretion of ptyalin and/or mucin into ducts.
Also NaCl, water and HCO3- are secreted
ISOTONIC SOLUTION

Question 12

Secondary process

Answer 12

As saliva movees through ducts;
- Na+ is actively absorbed into lining cells
- Cl- is passively absorbed
- K+ is actively secreted into lumen
HYPOTONIC SOLUTION

Question 13

Flow rate changes in composition of saliva

Answer 13

With slower flow rate, the amount of Na+ and Cl- in saliva will decrease as it has more time for absorbtion in secondary stage

Question 14

Parasymp nerve stimulus

Answer 14

causes an increased and watery secretion
impulses from CN VII and IX cause Ach to act on muscarinic receptors
Activates chlorine and potassium channels

Question 15

Simple reflex of salivation

Answer 15

• chemoreceptor and pressure receptros detect food in mouth
• simple reflex to salivary centre in medulla
• autonomic nerves
• use Ach as transmitter to salivary glands
• increase secretion of saliva

Question 16

Conditioned reflex of salivation

Answer 16

• thought, sight or smell of food
• sent to cerebral cortex
• sends impulses to salivary centre in medulla
• then same as simple reflex

Question 17

Symp nerve stimulus

Answer 17

mediated by B-adrenergic receptors

causes increased viscosity (mucus) saliva