• Mouth: Foodstuffs are broken down mechanically by chewing and saliva is added as a lubricant. In some species, saliva contains amylase, an enzyme that digests starch.
• Esophagus: A simple conduit between the mouth and stomach - clearly important but only marginally interesting compared to other regions of the tube.
• Stomach: Where the real action begins - enzymatic digestion of proteins initiated and foodstuffs reduced to liquid form.
• Liver: The center of metabolic activity in the body - its major role in the digestive process is to provide bile salts to the small intestine, which are critical for digestion and absorption of fats.
• Pancreas: Important roles as both an endocrine and exocrine organ - provides a potent mixture of digestive enzymes to the small intestine which are critical for digestion of fats, carbohydrates and protein.
• The Gall Bladder:
•     The gall bladder is a pouch-shaped organ which lies near the liver. It accepts bile from the liver, and stores it. When food is digested, the gallbladder releases bile into the small intestine where it is able to help dissolve fats.
• Small Intestine: The most exciting place to be in the entire digestive system - this is where the final stages of chemical enzymatic digestion occur and where almost almost all nutrients are absorbed.

o Jejunum The jejunum is the next portion of the small intestine, and it has a lining which is specialized in the absorption of carbohydrates and proteins. The proteins have been broken down in the stomach by enzymes called pepsin and acid into amino acids. The carbohydrates are broken down in the duodenum by enzymes from the pancreas and liver into sugars. Fats are broken down in the duodenum by "lipase" from the pancreas into fatty acids. Amino acid, sugar, fatty acid particles, vitamins, minerals, electrolytes and water are small enough to soak into the villi of the jejunum and drop into the blood stream. The blood takes all these nutrients to all the other...