1. Digestive System Complex job of moving and breaking down food

2. The body needs energy and materials  Nutrients  Important substances that enable the body to move, grow, and maintain homeostasis.  Protein – used for growth and repair  Carbohydrates-provide energy  Fats-stores energy  Water-helps carry out chemical processes

3. Digestive System  Digestion  The process of breaking down food in smaller substances that your body can use.

4. Two types of Digestion  Mechanical Digestion  Physical or mechanical changes  Usually breaking the food into smaller pieces  Chewing  Stomach mashing and pounding  Peristalsis  Wavelike contractions of smooth muscle tissue in your digestive system  Chemical Digestion  Breaking down of food by a chemical process  Saliva  Stomach acid

5. Traveling in the Digestive System  Mouth  Mechanical and Chemical digestion  Teeth, Tongue, Salivary glands  Esophagus  Mechanical Digestion (Peristalsis)  Stomach  Mechanical and Chemical digestion  Muscles in stomach mix and mash  Strong Stomach acids break down food  Small Intestine  Chemical digestion  Most of nutrients are absorbed in small intestine  Villi absorb nutrients  Large Intestine  Water and small amounts of nutrients are absorbed  Solid waste material stored until eliminated through rectum

6. Other Organs involved in Digestion  Salivary Glands  Produce saliva to begin chemical digestion  Liver  Filters blood  Stores unneeded nutrients for later use  Produces bile to break down fats  Breaks down medicines  Gallbladder  Stores bile  Pancreas  Produces chemicals that reduce acid in small intestine  Produces digestive chemicals that prepare nutrients to be absorbed.