The Esophagus T his is a muscular tube that sends swallowed food to the stomach. The walls of the esophagus flatten out when not in use. The Stomach T his J-shaped organ provides a connection between the esophagus and the small intestine. Hydrochloric acid is secreted in the stomach as part of the digestive process. This acid is strong enough to dissolve steel, and, in addition to causing heartburn, it kills bacteria from the ingested food that it is working on.
Food remains in the stomach for about four hours .
The Small Intestine T he small intestine is where most enzymatic digestion and most nutrient absorption occurs. Most digestive enzymes that work here are actually from the pancreas. The major large intestine function is to separate water and electrolytes from the remaining semisolid mass, which is slowly, but inexorably, being propelled toward its final destiny. Its digestive function is to produce bile - a green, alkaline liquid. The liver also does many metabolic jobs.