Parts of the Digestive System


Your digestive system is made up of the gastrointestinal tract that extends from your mouth, where food enters your body, to the anus, where food waste exits. Let’s look at some components of the digestive system in more detail.

Gastrointestinal Tract

MouthOral Cavity

Your mouth, the external part of the oral cavity, is the entrance for all food that enters your body. Your lips are at the opening of the oral cavity, which is surrounded by your cheeks. Inside the oral cavity are your teeth and tongue, which is actually a large muscle.

ThroatPharynx

Food leaving your mouth enters your throat, also called the pharynx. At its opening, the pharynx divides into two pathways. One pathway carries air to your lungs, and the other pathway carries food and drink to your esophagus, which leads to your stomach.  In this section we are only concerned with the pathway to your stomach. When you swallow, a flap called the epiglottis covers the pathway leading to your lungs so that food is directed into your esophagus.

Esophagus

Your esophagus is a tube about 10 inches long that connects your pharynx to your stomach. Food enters from the pharynx and slowly travels down by muscle contractions to your stomach.

Stomach

Your stomach is located in the upper left portion of your abdomen, beneath your liver.  The size of the stomach varies in each person and changes depending on when they last ate. The stomach is the size of a large sausage when it is empty, but it enlarges as food enters.

Pancreas

Your pancreas is 6 to 9 inches long, and is located behind your stomach. As a digestive organ, the pancreas releases enzymes that help digest food.

Liver

Your liver is located above your stomach, just under your rib cage. It is a reddish-brown organ with unequally sized lobes, or rounded portions. The liver is the largest internal organ in your body and weighs a little over 3 pounds in an average adult. The liver makes bile, a detergent that helps break down fats.

Gallbladder

Your gallbladder is a much smaller organ located directly beneath your liver. Its function is to store the bile that your liver makes.

Small Intestine

Your small intestine is located in the middle of your abdomen. It is about 1 inch in diameter, and it coils around itself to fit into your body. If you were to elongate the small intestine, it would be about 20 feet in length.

Large Intestine

Your large intestine makes one big loop around your small intestine. It is larger than the small intestine in diameter, thus its name, but considerably smaller in length at only about 5 or 6 feet long. This organ is divided into several sections, including the colon and the rectum.

Anus

The anus refers to the opening at the end of your gastrointestinal tract where bodily waste or feces are excreted.