What are the parts of the digestive system?

Big Question:

The esophagus is the tube that connects the throat (pharynx) with the stomach. The esophagus is about 8 inches long, and is linked by moist pink tissue called mucous. The esophagus runs behind the windpipe (trachea) and the heart, and in front of the spine.Just before entering the stomach, the esophagus passes through the diaphragm.

The liver is a large, meaty organ that sits on the right side of the belly. Weighing about three pounds, the liver is reddish-brown in color and feels rubbery to the touch. Normally you can’t feel the liver, because, it is protected by the ribcage. The liver has two large sections, called the right and left lobes.

The stomach is a muscular organ located on the left side of the upper abdomen. The stomach receives food from the esophagus. As food reaches the end of the esophagus, it enters the stomach through a muscular valve called the lower esophageal sphincter. The stomach secretes acid and enzymes that digest food.

The gallbladder is a small pouch that sits under the liver. The gallbladder stores bile produced by the liver. After meals, the gallbladder is empty and flat, like a deflated balloon. Before the meal, the gallbladder may be full of bile and about the size of a small pear. In response to signals, the gallbladder squeezes stored bile into the small intestine through a series of tubes called ducts.

The small intestine is a winding, folded tube about 20 ft(6m) long in adults. It connects to the stomach on the top end and to the large intestine(colon) on the bottom end. Most of the food a person absorbs is digested and absorbed in the small intestine. The lining of the small intestine has tiny, finger-shaped tissue(villi). These raised tissues greatly increase the surface area of an intestine, which absorbs calories and nutrients from food.