Digestive system
= Digestive system
The <digestive system> processes <food>, absorbs usable material and eliminates residual contents. The alimentary tract works with accessory <organs> such as the <liver>, <pancreas> and <gallbladder>. Mechanical processing, chemical breakdown and transport across an <epithelium> are distinct functions.<Regions of the Digestive System by the National Cancer Institute>[Alimentary tract and accessory organs]{ref}