The digestive system is a group of organs working together to convert food into energy and basic nutrients to feed the entire body. The digestive system of the head and neck contains the structures responsible for the ingestion, chewing, swallowing, and initial digestion of food. These structures include the parts of the mouth, the salivary glands that produce saliva, and the pharynx.
The esophagus is a long, thin, and muscular tube that connects the pharynx (throat) to the stomach. It forms an important piece of the gastrointestinal tract and functions as the conduit for food and liquids that have been swallowed into the pharynx to reach the stomach.The esophagus is about 9-10 inches (25 centimeters) long and less than an inch (2 centimeters) in diameter when relaxed.The esophageal muscles line the esophagus just above the point where it joins the stomach. The circular muscle fibers in the esophageal muscle walls are thickened.
The stomach is the main food storage tank of the body. If it were not for the stomach’s storage capacity, we would have to eat constantly instead of just a few times each day.The stomach also secretes a mixture of acid, mucus, and digestive enzymes that helps to digest and sanitize our food.The stomach is a rounded, hollow organ located just inferior to the diaphragm in the left part of the abdominal cavity.
Weighing in at around 3 pounds, the liver is the body’s second largest organ; only the skin is larger and heavier. The liver performs many essential functions related to digestion, metabolism, immunity, and the storage of nutrients within the body.These functions make the liver a vital organ without which the tissues of the body would quickly die from lack of energy and nutrients.
The gallbladder is a small storage organ located inferior and posterior to the liver. Though small in size, the gallbladder plays an important role in our digestion of food.The gallbladder holds bile produced in the liver until it is needed for digesting fatty foods in the duodenum of the small intestine.