Question

Write 5 functions of saliva.

Answer 1

Hint: Saliva is defined as the extracellular fluid that is produced and secreted by the salivary glands present in the mouth. The use of saliva is different in different species.

Complete answer:
The saliva in humans comprises of water 99.9% along with many other electrolytes such as potassium, sodium, calcium, phosphate etc., mucus consisting of glycoprotein and mucopolysaccharides, antibacterial substances such as hydrogen peroxide, lysozyme and thiocyanate and many essential enzymes such as amylase, lipase, etc. five function of saliva are as follows-
- Saliva is known to coat the oral mucosa and serve as a lubricant that protects the mucosa during speaking, eating as well as swallowing.
- Saliva plays an important role in imparting the sense of taste by carrying the chemicals to the taste receptor cells of the mouth.
- Saliva helps in maintenance of the pH of the mouth since it contains several ions that act as buffers thus maintaining a constant pH.
- Saliva plays a major role in the early step of digestion, it moistens the food and helps in the creation of a bolus which enables the food to be easily passed through the esophagus. Saliva also consists of enzyme amylase that breaks down starch into simpler sugars.
- Saliva is known to secrete the enzyme carbonic anhydrase that plays important role in the development of the taste buds of the mouth.

Note: Though the major roles of saliva are mentioned above, it also plays several other roles such as the saliva of cobra and vipers are known to be venomous and can kill humans and some caterpillars produce silk fibers from their modified salivary glands.