This is analogous to food that remains in the large intestines for the same length of time. Basically, the alimentary system is where digestion of food takes place. Food is broken down into smaller molecular particles that can be transmitted by the blood system to the various tissues and organs for the production of energy and cells. At the cecum is found the ileo-cecal valve, a sphincter which controls the flow from the small intestines. The colon has a smooth mucous lining with circular internal muscles and longitudinal external muscles.
Water is removed, reducing the chyme to a semi-solid consistency called feces.
Bacterial action plays a major role in nutrition and digestion. Friendly bacteria synthesize valuable nutrients by digesting portions of the fecal mass. Vitamin K, portions of the B-complex, and other vitamins are produced. Any remaining proteins are broken down by the bacterial and fungal flora. The normal bacterial flora can easily be destroyed by antibiotics.