saliva
Saliva, also known as mouth saliva, saliva, is the animal oral salivary glands secrete colorless and thin liquid, which in the food digestion process plays a very critical role. Although saliva in ancient times known as the "Jin Jin Yu liquid", in the modern but always gives a sense of disgrace, resulting in "reviled" the word, said the humiliation of people. Saliva is mainly secreted by the three salivary glands of the parotid gland, submandibular gland and sublingual gland. The secretion of saliva is controlled by the cerebral cortex and is affected by diet, environment, age and mood or salivary gland. Human daily secretion of 1,000-1,500 ml of saliva is normal. Infants are more saliva than adults. Some animals' saliva has other effects in addition to being involved in digestion. For example, swallows will use saliva to help nest, which swift or swiftlet's nest is the bird's nest. ...