Detail study of Salivary glands
- Submandibular or submaxilary glands
- Sublingual glands
Salivary glands
Salivary gland is an exocrine gland.
It releases a secretion of saliva in oral cavity. It is important to clean mouth and keep moist the mouth and pharynx.
when the food s entered into the mouth the tactile receptors sense it and promote salivary glands.
Even when we think about the food the salivary secretion increase from glands.
Saliva lubricates, dissolves and starts chemical breakdown of the food material.
The salivary glands present in the mouth and tongue.
There are some minor salivary glands including labial, buccal and palatal glands present in lips, checks and palate and lingual glands in the tongue.
Most of the saliva is secreted by major salivary glands. There are 3 pairs of major salivary glands
1. Parotid glands
2. Submandibular or submaxilary glands
3. Sublingual glands
Parotid glands
The parotid glands are located anterior and inferior to ear between skin and masseter muscle.
The parotid gland secretes saliva to oral cavity through parotid duct or duct of stenson that opens in the second upper molar tooth.
The parotid glands secret salivary amylase or diastase or ptyalin. It digests cooked starch into maltose and isomaltose.
Submandibular gland or submaxilary gland
It present in the floor of the mouth.
It secretes saliva into oral cavity through Submandibular duct or duct of Wharton and open to the lingual frenulum near lateral incisors.
It secretes fluid containing thick amylase with mucous.
Sublingual gland
The Sublingual glands are present under the tongue superior the Submandibular glands.
It secrets the saliva to oral cavity through the lesser Sublingual ducts or duct of rivinus.
It secretes mostly thick mucus and a small quantity of salivary amylase.
Composition and function of saliva
Saliva consists 99.05% water and 0.5% solute.
The solute part of saliva includes sodium, potassium, chlorine and phosphorous etc.
It gives a medium for dissolving food so that we can taste the food and start the digestive reaction.
The saliva also contains some gasses and organic substances like urea, uric acid, mucus, Immunoglobulin A, lysozyme, and salivary amylase.
Secretion of saliva is a reflex action, in response to taste of food it is inborn reflex or inherited reflex and in response to smell, thought, feel, sight of food it is acquired reflex.
Sympathetic nervous system decreases secretion of saliva.
Parasympathetic nervous system increases secretion of saliva.
During sleep the secretion of saliva decreases so the bacterial activities increases.
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