Saliva Research Paper

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Physiology Of Saliva
Introduction
The volume of saliva secreted per day is 1000 mL to 1500 mL. When awake the rate is approximately about 1 mL/min but when asleep little secretion of saliva occurs. The major salivary glands are the parotid gland, the submaxillary gland and the sublingual gland. Also, there are many tiny buccal glands.
Composition Of Saliva
Mixed saliva contains 99.5% water and 0.5% solids. The composition of saliva varies with salivary flow rate. The components interact and are responsible for the various functions of saliva

Organic Substances
Mucins
Mucins are elaborate glycoproteins, found as high and low molecular weight mucins (MC1&2).
Mucins give saliva its lubrication properties. Mucins form homotypic complexes making …show more content…

When food is taken into the mouth, it is moistened and dissolved by saliva. Saliva has three digestive enzymes, namely salivary amylase, maltase and lingual lipase.

Amylase (ptyalin)
It acts on starch and converts it into dextrin,maltose and maltotriose favoring the formation of the food bolus. Though starch digestion starts in the mouth, major part of it occurs in stomach because, food stays only for a short time in the mouth..Saliva has a pH between 6.0 and 7.0, a favorable range for the digestive action of ptyalin (amylase). It is inactivated in the stomach due to the low pH.
Lingual Lipase
Lingual lipase is a lipolytic enzyme. It is secreted from serous glands situated on the behind the tongue. It digests pre-emulsied fats by hydrolyzing triglycerides into fatty acids and glycerol
• The constant secretion of saliva washes off food debris and shed epithelial cells from teeth and out of the oral cavity serves as a protective function. By removing these materials saliva they prevent bacterial growth. However if bacterial growth still occurs saliva has further protective functions. Saliva has antimicrobial proteins which will kill the bacteria reducing risk of dental caries and periodontal infection. There are two types of antimicrobial …show more content…

Ex. glucose in diabetes mellitus. Or substances found in saliva are excreted in large quantities. Ex. excess urea during nephritis and excess calcium is excreted during hyperparathyroidism.
Regulation Of Body Temperature
In dogs panting helps in the loss of heat. However, in humans this doesn’t occur but the below occurs.
Regulation Of Water Balance
When the body is dehydrated, salivary secretion is reduced as there is less water. This causes dryness of the mouth and induces thirst. This thirst is quenched by intake of water resulting in the restoration of body water content.
Cools Hot Food
Since its soluble, it dilutes hot food reducing the possibility of damaging the mucosa. It also moistens dry food.
Appreciation Of Taste
Also since its soluble, saliva dissolves the solid food substances which can now stimulate the taste receptors.

Tissue Repair
The time taken for saliva to coagulate is accelerated compared the other tissues, although the resulting clot is less solid than normal. In investigative studies in mice it was seen that in the presence of saliva wound contraction is much faster due to the epidermal growth factor which is produced by the submandibular

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