How Do Use Digest Our Food?
To keep us alive and growing, taking food into our body is not enough. The food must be changed so that it can be used by the body, and this process is called digestion.
Digestion starts, the movement we put food in the mouth, chewed and swallowed, and it continues in the alimentary canal. It is a longs partly coiled tube going through the body. All parts of the alimentary canal are joined together, but they are different in the way they work. The mouth opens into a “Pharynx” in the throat which is a passage used for both food and air. The “esophagus”‘ rough the chest and connects the pharynx and stomach. The stomach leads into the coiled “Small intestine”. The last part of the alimentary canal is the “colon” or “large intestine”.
The picture shows, what happens to food during digestion. In mouth, the saliva helps to break down starches, like those in corn and starches. After the food is moistened and crushed in the month, it goes down through pharynx and along the esophagus, and finally it goes enters the stomach.
Most of the digestion process takes place in stomach. Juices stomach wall are mixed with the food. Hydrochloric acid is one of the juices Pepsin, another secretion, helps to break down proteins into simpler forms to aid digestion. Until the material in the stomach becomes too acidic, the starches continue to break up. The digestion of starches stops at this stage.
Until its liquid, the food stays in stomach. The material in the stomach is churned. Digestive juices are mixed in the food thoroughly. The food is called “chyme” when it is liquified. The chyme moves out from the stomach into the small intestine through a valve at the lower end of the stomach, the “pylorus”.
The small intestine is a tube 7 to 8 metres in length. It lies in coils. In “duodenum”, the first part of the small intestine tube digestion continues. Juices from the pancreas and liver help break down the foods. The break-down of proteins is finished here, the fats are further spilt into finer parts, the starch digestion is completed here into the blood and lymph. In the large intestine, water is absorbed and the contents become more solid, so they can leave the body as waste material.
