Salivary Glands and Saliva

Saliva is composed of 97 to 99.5% water. The remaining proportion includes enzymes such as lipases and amylases, electrolytes, dissolved gasses, IgA, mucin, lysozymes, and metabolic wastes like urea and uric acid.

Saliva primarily functions to dissolve food and initiate the digestion of carbohydrates through salivary amylases.

Additionally, it neutralizes acidic foods and hinders bacterial proliferation in the oral cavity.

The glands that produce saliva are called the salivary glands. 

The intrinsic salivary glands, scattered throughout the mouth, produce minimal saliva.

The extrinsic salivary glands — parotid, submandibular, and sublingual — produce most of the saliva.

These extrinsic glands release their secretions through their independent ducts.

The parotid glands, located near the ears, secrete a serous solution rich in salivary amylase.

The submandibular glands, located on the floor of the mouth, release a mucus-heavy liquid with amylase.

Finally, the sublingual glands, situated beneath the tongue, release a thick fluid with minimal amylase.