Brian Hughes age 10, of South Williamsport, Penn., for his question:

WHERE DOES SALIVA COME FROM?

Saliva is a sticky fluid that is produced in the mouth. It is important to the digestion of your food. Saliva has a colorless and water appearance. It contains some mucus and it produces an alkaline, or acid neutralizing chemical action. It also contains the enzyme called ptyalin which changes starches into simpler substances called maltose.

Three pairs of glands in the cheeks and mouth, known as salivary glands, produce saliva. One pair is located in front of the ears, another under the lower jaw and the third pair of glands is located under the tongue. There are several other small glands in the mucous membrane of the mouth that also aid in the production of saliva.

Saliva helps in the chewing and swallowing of food. it also keeps the mouth moist and comfortable.