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Renin Angiotensin Mechanism.

Salivary Glands.

 

Salivary Glands:

  • These exocrine glands secrete a secretion called saliva in the oral cavity.

  • There are 3 pairs of the salivary glands,

  1. Parotid Glands.

  2. Submandibular glands.

  3. Sublingual glands.

  • Parotid glands:

    • Largest salivary glands.

    • Present below the ears.

    • Secrete saliva in the oral cavity through parotid ducts.

    • Saliva contains large amounts of Salivary amylase.

    • More fluidity in nature.

  • Submandibular Glands:

    • Present below the mandible.

    • Secrete saliva in the oral cavity through submandibular ducts.

  • Sublingual Glands:

    • Smallest salivary glands.

    • Present below the tongue.

    • Saliva contains less amount of salivary amylase.

    • Thick in nature.

Saliva:

  • Secretion of salivary glands is called “Saliva”.

  • It is colorless.

  • It is 99.5% water and remaining .5% is inorganic salts, enzymes and waste materials like urea, uric acid etc.

  • Saliva has a slight acidic pH 6.35 to 6.85.

  • Saliva contains an enzyme “Salivary amylase (Ptyline)”.

  • Daily secretion is 1 to 1.5L.

  • Functions:

  1. Lubrication of the mouth.

  2. Lubrication and moistening of food.

  3. Continuous flushing and cleaning of the oral cavity helps check microbial growth.

  4. Many drugs and waste materials are excreted via saliva.

  5. Salivary amylase causes chemical digestion of starch.

Commonly Asked Questions.

  1. Write a note on Salivary Glands.

  2. Give composition and functions of Saliva.
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