The Digestive System (simplified!)

Learning Goals I will be able to explain how food is digested and nutrients absorbed into the body

Let’s learn how our body digests food. Digest means to break down food in the body.

Esophagus When you chew your food, it mixes with a liquid in your mouth called saliva. Saliva helps break down food. Once food has been chewed and swallowed, it goes down a tube called the esophagus.

Stomach Once the food goes down the esophagus, the food enters the stomach. The stomach continues to break down the food. It has muscles that mash food into a sloppy soup.

Large and Small Intestines Food leaves the stomach and enters the small intestine. Nutrients your body needs from the food you eat goes to all parts of the body. You have about 20 feet of small intestines. Food that your body does not need goes to the large intestine. L S

Digestive System Digestion begins when food enters the mouth where saliva and teeth break it down. Once food has been chewed and swallowed, it goes down a tube called the esophagus to the stomach. Stomach muscles mix the food and moves it to the small intestine. Food that your body does not need goes to the large intestine.

Using Nutrients Once food has been broken down into nutrients, digestion is complete You body still has work to do though It must absorb the nutrients and take them to where they can be used or stored

Absorption Nutrients are absorbed into the bloodstream Most absorption takes place in your small intestine

Processing and Storing Nutrients After absorption, nutrients are carried through a blood vessel called the portal vein to the liver One of the livers jobs is to turn nutrients into forms the body can use Example: Converts amino acids into different kinds of proteins The proteins are then carried by the blood to where they are needed

Processing and Storing Nutrients If not needed immediately nutrients are stored Example: Extra glucose is converted by the liver into glycogen Stored in the liver and in muscles If there is more than can be stored it is converted to body fat Fats are then deposited throughout the body as and energy reserve

Processing and Storing Nutrients Minerals are stored in various ways Some examples: Iron is stored in the liver and bone marrow Fat-soluble vitamins are stored mainly in the liver and body fat

READ A Letter To the Digestive System (It’s a PDF)

It’s not just the digestive system though!!! Nutrients affect the whole body including (but not limited to): Nervous system Circulatory system Immune system Endocrine system (hormones) Your turn! The Task: A Letter of Complaint similar in style to the Digestive System Letter. Don’t forget your citations!!!!