Esophagus                                                 Duodenum, jejunum and ileum are the
                                                           three major region of small intestine.
  The esophagus is a long, thin, and
   muscular tube that connects the pharynx            Liver
   (throat) to the stomach.
  It functions as the conduit for food and               It is a roughly triangular accessory organ
   liquids that have been swallowed into the               of the digestive system located to the right
   pharynx to reach the stomach.                           of the stomach, just inferior to the
  It is about 9-10 inches (25 centimeters)                diaphragm and superior to the small
   long and less than an inch (2 centimeters)              intestine.
   in diameter when relaxed.                              Weighing in at around 3 pounds (1.36 kg)
  At the inferior end of the esophagus is a               , the liver is the body’s second largest
   muscular ring called the lower esophageal               organ.
   sphincter or cardiac sphincter. It is used to          It helps in digestion, metabolism,
   close of the end of the esophagus and trap              immunity, and the storage of nutrients
   food in the stomach.                                    within the body.
Stomach                                               Gallbladder
  It is the main food storage tank of the            It is a small, pear-shaped organ located just
   body, so that the body has time to digest          posterior to the liver. It is used to store and
   large meals properly.                              recycle excess bile from the small intestine so
                                                      that it can be reused for the digestion of
  It is a muscular sac that is located on the
                                                      subsequent meals.
   left side of the abdominal cavity, just
   inferior to the diaphragm.                         Pancreas
  It also contains hydrochloric acid (HCL)
   and digestive enzymes that continue the                It is a glandular organ in the upper
   digestion of food that began in the mouth.              abdomen, but really it serves as two glands
  The inner layer of the stomach is full of               in one: a digestive exocrine gland and a
   wrinkles known as rugae (or gastric                     hormone-producing endocrine gland.
   folds). Rugae both allow the stomach to                It is a narrow, 6-inch long gland that lies
   stretch in order to accommodate large                   posterior and inferior to the stomach on
   meals and help to grip and move food                    the left side of the abdominal cavity.
   during digestion.                                      The head of the pancreas, which connects
                                                           to the duodenum, is the widest and most
Small Intestine                                            medial region of the organ.
  It is a long, thin tube about 1 inch in                The tail of the pancreas extends from the
   diameter and about 10 feet long that is part            body as a narrow, tapered region on the
   of the lower gastrointestinal tract.                    left side of the abdominal cavity near the
                                                           spleen.
  It is located just inferior to the stomach
   and takes up most of the space in the                  Glandular tissue that makes up the
   abdominal cavity.                                       pancreas gives it a loose, lumpy structure.
  It is coiled like a hose and the inside            Large Intestine
   surface is full of many ridges and folds.
  It absorbs about 90% of the nutrients from             It is the final section of the gastrointestinal
   the food.                                               tract.
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