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According to the KidsHealth - the Web's most visited site about children's health, the digestive system helps the body to break down and absorb food. It’s a system that is made up of a series of hollow organs joined from the mouth to the anus. Its organs that make up the digestive are the following: mouth, esophagus, stomach, small intestine, large intestine and anus. Inside these hollow organs is a lining called the mucosa. In the mouth, stomach, and small intestine, the mucosa contains tiny glands that produce juices that help us to digest the food we eat.
It also contains a layer of smooth muscle that helps us break down food and move it along the tract. The liver and the pancreas are the two “solid” digestive organs that produce digestive juices that reach the intestine through small tubes called ducts. The gallbladder stores the liver’s digestive juices until they are needed in the intestine. The nervous and circulatory systems also play major roles in parts of the digestive system.
The digestive system is important just like any other system in our body, especially when it involves food. Food and drink are not in a form that the body can use as nourishment. That’s why the food and drink must be changed into smaller molecules of nutrients before they can be absorbed into the blood and carried to cells throughout the body. That’s where the digestive system comes in. Digestion is the process by which food and drink are broken down into their smallest parts so the body can use them to build and nourish cells and to provide energy.
According to Medical Library of Medem, digestion involves mixing food with digestive juices, moving it through the digestive tract, and breaking down large molecules of food into smaller molecules. Digestion begins in the mouth, when you chew and swallow; it becomes involuntary and proceeds under the control of the nerves, and is completed in the small intestine. Swallowed food is pushed into the esophagus, which connects the throat above with the stomach below. The stomach has three mechanical tasks. First, it stores the swallowed food and liquid. To do this, the muscle of the upper part of the stomach relaxes to accept large volumes of swallowed material.
second job is to mix up the food, liquid, and digestive juice produced by the stomach. The lower part of the stomach mixes these materials by its muscle action. The third task of the stomach is to empty its contents slowly into the small intestine. Finally, the digested nutrients are absorbed through the intestinal walls and transported throughout the body. The waste products of this process include undigested parts of the food, known as fiber, and older cells that have been shed from the mucosa. These materials are pushed into the colon, where they remain until the feces are expelled by a bowel movement (American Dietetic Association).