The Digestive System

https://raw.githubusercontent.com/qknow/images/gh-pages/primary/class-6-science/digestive system.jpg

The function of the Digestive System is digestion and absorption. The Digestive System breaks down food into small molecules, which are then absorbed into the body. In addition, after this process, the leftover food that isn't digested gets all of the water absorbed from it and then the remaining useless material, is eliminated from the body.

The major organs in the Digestive System are:

Esophagus: The purpose of the Esophagus is to carry food, liquids, and saliva from the mouth to the stomach.

Stomach: The main function of the Stomach is to break down and digest food. This has to happen in order for the necessary nutrients to be extracted from the consumed food. In addition, the Stomach plays a part in producing various enzymes. These enzymes include pepsin and acid.

Small Intestine: The major function of the Small Intestine is to absorb nutrients and minerals from the digested food. The Small Intestine absorbs the nutrients and minerals into the blood stream.

Large Intestine: The Large Intestine absorbs water from the remaining, undigested food and transmits or sends out the useless leftover waste from the body.

The Digestive System works with the Circulatory System and the Excretory System. The Digestive System works with the Circulatory System to get the absorbed nutrients that the Digestive System broke down, distributed throughout the body. In addition, the Circulatory helps the Digestive System by carrying chemical signals from the Endocrine System that control the speed of digestion. The Digestive System works with the Excretory System to control the amount of water in the body. As the Digestive System collects and gets rid of undigested material, the Excretory System filters compounds from the blood stream and then gathers them in urine.

Analogy

http://www.nature.org/cs/groups/webcontent/@web/@lakesrivers/documents/

media/iliamna-lake-ak-splash.jpg

The esophagus of the Digestive System is like a river because:

• it acts as a pathway
• it links to areas together
• it carries and moves material from one place to another

The esophagus is like a river because both act as pathways that carry and move material from one place to another. The esophagus carries the food from the mouth to the stomach just as a river brings water from lakes to oceans. Also, the esophagus links the mouth to the stomach just like how a river links a lake to an ocean.

Structure and Function

The main function of the mouth is to chew food to break it down into pieces that are more easy for the body to digest. The mouth contains the structures of teeth, tongue, tonsils, and salivary glands. These structures assist in performing the mouth's functions. I believe that because all of these structures are present in the mouth, it is the reason the mouth can break down food easily. Because teeth are present in the mouth, it helps make breaking down food much easier because of chewing. In addition, I believe that because salivary glands are inside the mouth, it helps mix saliva with the broken down food which makes digesting the material easier.

Sources:
www.biology4kids.com/files/systems_digestive.html

http://kidshealth.org/en/kids/digestive-system.html