The food goes into the mouth where chemical and mechanical digestion starts.
Saliva from the glands in the bottom and the back of the jaw is added for chemical
digestion. Your teeth and tongue start the mechanical digestion by crushing and
tearing the food apart. The mashed food is then passed through the stomach, via
peristalsis, and into the stomach. The sphincter, at the bottom of the esophagus,
stops food from re-entering the esophagus and regurgitating. In the stomach several
acids and enzymes, made in the walls of the stomach, are added to break down
proteins, carbohydrates, etc. The lining is surrounded by mucus to protect the
smooth muscle that mechanically stirs the stew. Once the food has been broken
down enough it is called chyme, a thick soup. At this stage the chyme passes out of
the stomach and into the duodenum, the first 35 centimeters of the stomach. Here,
in the small intestine, pancreatic juices from the pancreas and bile from the liver
collect in the gall bladder. This mixture is the passed through the bile duct and out
the pancreatic duct into the small intestine. These chemicals break food down even
further so it can be absorbed by the minute capillaries in the tiny villi that line the
small intestine. Nutrients and minerals are taken by the blood stream throughout the
body for nourishment, repair, etc. All of the left over water, fruit skins and minerals
is now passed into the large intestine, the final step in digestion. Here water and all
other absorbable nutrients are taken away. If too much water is absorbed you can
become constipated, too little and you could have diarrhea. The remaining feces are
taken into the rectum and passed out of the anus, leaving the body.