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Human Digestive System
Digestive System Label Me! Printout (Simple version)
Digestive System Label Me! Printout

digestive system The human digestive system is a complex series of organs and glands that processes food. In order to use the food we eat, our body has to break the food down into smaller molecules that it can process; it also has to excrete waste.

Most of the digestive organs(like the stomach and intestines) are tube-like and contain the food as it makes its way through the body. The digestive system is essentially a long, twisting tube that runs from the mouth to the anus, plus a few other organs (like the liver and pancreas) that produce or store digestive chemicals.

The Digestive Process:
The start of the process - the mouth: The digestive process begins in themouth. Food is partly broken down by the process of chewing and by the chemical action of salivary enzymes (these enzymes are produced by the salivary glands and break down starches into smaller molecules).

On the way to the stomach: the esophagus - After being chewed and swallowed, the food enters the esophagus. The esophagus is a long tube that runs from the mouth to the stomach. It usesrhythmic, wave-like muscle movements (called peristalsis) to force food from the throat into the stomach. This muscle movement gives us the ability to eat or drink even when we're upside-down.

In the stomach - The stomach is a large, sack-like organ that churns the food and bathes it in a very strong acid (gastric acid). Food in the stomach that is partly digested and mixed with stomach acids iscalled chyme.

In the small intestine - After being in the stomach, food enters the duodenum, the first part of the small intestine. It then enters the jejunum and then the ileum (the final part of the small intestine). In the small intestine, bile (produced in the liver and stored in the gall bladder), pancreatic enzymes, and other digestive enzymes produced by the inner wall of the smallintestine help in the breakdown of food.

In the large intestine - After passing through the small intestine, food passes into the large intestine. In the large intestine, some of the water and electrolytes (chemicals like sodium) are removed from the food. Many microbes (bacteria like Bacteroides, Lactobacillus acidophilus, Escherichia coli, and Klebsiella) in the large intestine help in thedigestion process. The first part of the large intestine is called the cecum (the appendix is connected to the cecum). Food then travels upward in the ascending colon. The food travels across the abdomen in the transverse colon, goes back down the other side of the body in the descending colon, and then through the sigmoid colon.

The end of the process - Solid waste is then stored in the rectum untilit is excreted via the anus.

Digestive System Glossary:
abdomen - the part of the body that contains the digestive organs. In human beings, this is between the diaphragm and the pelvis
alimentary canal - the passage through which food passes, including the mouth, esophagus, stomach, intestines, and anus.
anus - the opening at the end of the digestive system from which feces (waste) exits thebody.
appendix - a small sac located on the cecum.
ascending colon - the part of the large intestine that run upwards; it is located after the cecum.
bile - a digestive chemical that is produced in the liver, stored in the gall bladder, and secreted into the small intestine.
cecum - the first part of the large intestine; the appendix is connected to the cecum.
chyme - food in the stomach thatis partly digested and mixed with stomach acids. Chyme goes on to the small intestine for further digestion.
descending colon - the part of the large intestine that run downwards after the transverse colon and before the sigmoid colon.
digestive system - (also called the gastrointestinal tract or GI tract) the system of the body that processes food and gets rid of waste.
duodenum - the first...