The esophagus is a strait tube about 25 centimeters long.Its function is to provide a passageway for substances from the pharynx to the stomach.It penetrates the diaphragm through an opening and is continuous with the stomach on the abdominal side.Circular muscle fibers at the distal end help prevent the regurgitation of food from the stomach.
The liver is located in the upper right and central portions of the abdominal cavity, just below the diaphragm and is partially surrounded by the ribs.It is reddish brown in color and well supplied with blood vessels.The functions of the liver include maintaining the normal concentration of blood glucose. The liver's effects on lipid metabolism include oxidizing fatty acids at an especially high rate.The liver also deaminates amino acids, synthesizing various blood proteins, including several that are necessary for blood clotting.
The large intestine is divided into 4 sections-the ascending, transverse, descending, and sigmoid colons.The large intestine has little or no digestive function unlike the small intestine, however it secretes mucus.The rate of mucus secretion is controlled by mechanical stimulation and parasympathetic impulses.The absorption into the large intestine is generally limited to water and electrolytes.Many bacteria inhabit the large intestine and may help the body by synthesizing certain vitamins.
The stomach is divided into cardiac, fundic body, and pyloric regions.The stomach receives food, mixes it with gastric juice, carries on a limited amount of absorption, and moves food into small intestine.