Entry 1:Digestion and Salivary Glands

Digestion is the breaking down of food in the body, into a form that can be absorbed and used or excreted. It is also the process by which the body breaks down food into smaller components that can be absorbed by the blood stream.The digestive system is made up of the digestive tract,which is a series of hollow organs joined in a long, twisting tube from the mouth to the anus,and to other organs that help the body break down and absorb food.Even before you eat, when you smell a tasty food, see it, or think about it, digestion begins.
Part 1:Salivary Glands
The salivary glands are part of the digestive system. They do not function mechanically, but subject to the control of the brain.There are 3 pairs of salivary glands, of which one is in the front ear, one under the tongue, and the last one under the lower jaw. One interesting fact about the largest salivary glands is that it secrates about 23,600 litres of saliva in a lifetime!Each salivary gland has a special job too. The parotid gland, which is also the largest one, secretes large quantities of watery saliva.The main purpose of this saliva is to dilute and to moisten the food well.Which of the salivary glands will produce the most saliva also depends on the food we take in. Lower glands will function when we are chewing on food which do not need to be moistened, and the parotid gland goes to work and produce large quantities of watery saliva for dry food. When the food is ready to be swallowed, the tongue then pushes a tiny bit of food called a bolus toward the back of your throat into the opening of the esophagus, the second part of the digestive tract. I shall continue on this in my next entry.

Information obtained from:1)http://digestive.niddk.nih.gov/ddiseases/pubs/yrdd/
2)http://en.wikipedia.org/wiki/Digestive_system
3)Encyclopedia:Tell Me Why
4)http://kidshealth.org/kid/htbw/digestive_system.html