Experiment 12: Salivary Digestion

99% water and >1% mucin

% composition of water and mucin in saliva

mucin

What is the chief solid that composes salive?

1. moistens mucous membrane

2. prevents tooth decay by cleansing of cariogenic carbohydrates

3. neutralizing lactic acid

Function of saliva

Parotid

Submaxillary

Sublingual

Hundreds of buccal

Glands that secretes saliva

Psychic, mechanical, and chemical factors

How does saliva flow stimulated?

Protein - mucin

Enzyme - ptyalin

What is the protein and enzyme present in saliva

Buccal cavity and extends in the fundic end of stomach

Where does salivary digestion takes place?

Hydrolysis of starch by salivary amylase (ptyalin)

What is salivary digestion

Phenolphthalein, litmus paper, and congo red

Indicators used in saliva reaction test

a. Violet

b. Red → Blue

c. Red w/ bubbles

Results of resting saliva to indicators:

a. Phenolphthalein

b. Litmus

c. Congo Red

a. Violet

b. Red → Blue

c. Red (upper part) and clear (lower part)

Results of stimulated saliva to indicators:

a. Phenolphthalein

b. Litmus

c. Congo Red

stimulated saliva

Which has a higher pH, stimulated saliva or resting saliva?

Paraffin

What material was used to stimulate saliva secretion

mucin

What is the chief constituent of mucus?

Mucin

This is a mucopolysaccharide or glycoprotein that is chief constituent of mucus

Coagulation due to heating

How is mucin formed?

HAc

What reagent was used for test for mucin?

Cloudy solution with white ppt

Positive result for test for mucin

Lubricate mouth and prevent bacterial build up

What is the function of mucin?

Calcium, chlorides, and phosphates

What inorganic matter is present in saliva?

a. White ppt of silver chloride

b. Yellow ppt of ammonium phosphomolybdate

c. Negative for saliva

d. Clear with moisture (calcium oxalate)

Positive result for test for inorganic matter:

a. Chlorides

b. Phosphate

c. Sulfates

d. Calcium

5.6-7.9

Normal pH range of saliva

a. Silver nitrate + HCl

b. Ammonium molybdate + HNO3

c. Barium chloride + HCl

d. Ammonium chromate

What reagent was used to test for inorganic matter:

a. Chlorides

b. Phosphate

c. Sulfates

d. Calcium

acetic acid

What was used to acidify saliva in test for inorganic matter?

1% starch paste

iodine

Reagents used in digestion of starch paste

Maltose

Responsible fo reducing action

10-20 mins

How long does starch transform to reducing sugar

acids

Which has the the greatest inhibiting power of saliva

If its acidic it will dissolve enamel producing dental caries

Why is saliva basic and not acidic?

HAc

Used to precipitate mucin out of saliva

chlorides and phosphates

Abundant inorganic salts found in saliva