By Sharon Fabian

The digestive system is the group of organs that breaks down food so that the body can use it. Food must be broken down all the way to its individual molecules to be useable. This involves a number of steps, and different organs to do different parts of the job.

Once food is broken down it provides energy for many essential body functions. It provides the energy for all of our physical activity such as walking, playing sports, working, and talking. It also provides the energy for other, more automatic, activities including breathing and thinking. Food provides the energy for the nerves, muscles, and organs, including the heart, to continue working. It provides the fuel to build and repair body tissues. Food energy is needed to regulate body organs and systems. It is the fuel that provides heat to keep our body temperature at a steady 98.6 degrees.

The digestive process begins in the mouth. There, the teeth and the muscles of the mouth begin the digestive process by breaking down the food into smaller bits. Saliva, produced by the salivary glands, begins to digest the food before it is even swallowed. Saliva and the other chemicals produced along the way to speed the digestive process are called digestive enzymes.

Next, muscles in the throat help swallow the food, and it passes through a long tube called the esophagus. The esophagus goes from the throat to the stomach. In the stomach, a digestive fluid called gastric juice mixes with the food. The stomach muscles toss the food and the gastric juices, and break down the protein parts of the food. Other parts of the food will not be broken down for several more hours.

Sample

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