The
digestive system includes the
digestive tract and various supportive structures and accessory glands. The tract begins at the oral cavity with the teeth and
tongue. The salivary glands release
saliva into the mouth to moisten food for swallowing. The tract continues down the throat to the
esophagus, through the
cardiac sphincter, and into the
stomach.
Acid and digestive enzymes are added to the food to produce
chyme. The chyme passes through the pyloric sphincter to enter the
small intestine. Digestive enzymes from the
pancreas and
bile from the
liver are added to the chyme. The process of
digestion and
absorption are completed in the small intestine. Wastes are carried through the ileoceccal
valve into the large intestine. The wastes are moved to the
rectum, from where they can be expelled through the
anus.
