Digestive System Facts – Human Body

As you know, humans need food to survive, but it isn’t just because it is yummy. Food is how the body gets vital nutrients and energy. The breaking down of food into these components is called digestion.

The digestive system is responsible for getting food into the body, breaking it down, and getting the leftover waste ready for disposal.

Many organs make up the digestive system. They are: the digestive tract, liver, pancreas, and gallbladder.

Human Digestive System

The Gastrointestinal Tract

The gastrointestinal tract, also called the GI tract, is not one organ. It is a series of organs that begins at your mouth and ends at your anus.

We all know that food enters the body through the mouth. Once in the mouth we use our teeth to break food into smaller pieces. The smaller pieces increase the surface area of the food and allow saliva to break down the food even more.

When the food is small enough, we use our tongue to swallow the food. This sends the food down to your stomach through the esophagus, but it doesn’t drop straight down. There are muscles in the esophagus that help pass the food down.

Your stomach’s main job is to hold food while enzymes break it down into a form that the body can use. An enzyme is a substance that the body creates to speed up a process.

When the food in your stomach is broken down enough, it passes through to the small intestine. If the small intestine was unwrapped, it would be 22 feet long.

The small intestine uses more enzymes to break down the food. When it is ready, the small intestine absorbs water and nutrients that used to be food through its walls. Once through the walls the water and nutrients enter the bloodstream where they are taken to different parts of the body. Anything not absorbed by the small intestine is considered waste and passes to the large intestine.

The large intestine is also called your colon. It is 6 feet long and connects the small intestine to the rectum. The colon makes the body’s waste easier for disposal. Waste in your colon begins as a liquid, but as it passes through water is removed and it becomes a solid.

Once the waste has passed through the large intestine it is stored in the rectum. The rectum stores the waste until the brain decides it can be disposed of. It then passes through the anus and leaves the body.

Cross section of circumvallate papilla

Liver, Pancreas, and Gallbladder

In addition to the GI tract, the digestive system also contains the liver, pancreas, and gallbladder.

The liver is an organ that does several jobs. For digestion, the liver absorbs nutrients from the small intestine. It then turns these nutrients into different chemicals that the body needs. The liver also acts as a filter and breaks down dangerous chemicals that have been absorbed by the small intestine.

The pancreas creates enzymes that the small intestine uses to break down food. It also makes insulin, a hormone that helps the body process sugar.

Bile is a dark greenish liquid that the small intestine uses to help break down food. The liver continuously makes bile, and it is stored in the gallbladder until it is needed.



Interesting Facts:

  • The esophagus is about 10 inches long
  • It takes about 36 hours for waste to pass through your colon
  • The appendix is an organ attached to your large intestine that serves no purpose