Digestion 3 functions of the digestive system: Breaks down food into molecules Absorbs molecules into the blood Eliminates wastes from the body Digestion- the process by which the body breaks down food. - Mechanical- food is physically broken down. Ex: Chewing food - Chemical- chemicals break foods down. Ex: Amylase breaking down starch.

Absorption- the. process by which. nutrients pass. through the wall Absorption- the process by which nutrients pass through the wall of your digestive system into your blood. Materials that are not absorbed are eliminated.

The Mouth Both mechanical and chemical digestion begin in the mouth. - The Digestive Process Begins Both mechanical and chemical digestion begin in the mouth.

The Mouth - The Digestive Process Begins The shape of an enzyme molecule is specific to the shape of the food molecule it breaks down. Here an enzyme breaks down a starch into sugars.

The Esophagus Esophagus- muscular tube that connects the mouth to the stomach. Epiglottis- flap of tissue that seals off the wind-pipe when you swallow. Makes food go down the esophagus instead of the wind-pipe. Mucus- thick, slippery substance produced by the body. Lines the esophagus. Peristalsis- wave-like motion caused by contractions of smooth muscles in the esophagus.

The Stomach Stomach- J-shaped muscular pouch located in the abdomen. Mechanical and chemical digestion happen in the stomach. - Mechanical digestion- churning - Chemical digestion- digestive juice *Pepsin- enzyme in digestive juice * Hydrochloric Acid- strong acid in digestive juice Stomach is lined with mucus, prevents stomach acid from burning the stomach cells.

The Stomach - The Digestive Process Begins Most mechanical digestion and some chemical digestion occur in the stomach.

Final Digestion and Absorption Small Intestine- part of digestive system where most chemical digestion takes place. In line after stomach. About 6 meters long. Named for its small diameter- 2 to 3 cm wide. Almost all chemical digestion and absorption takes place in the small intestine.

The Small Intestine - Final Digestion and Absorption The small intestine is the part of the digestive system where most chemical digestion takes place.

The Small Intestine - Final Digestion and Absorption Tiny finger-shaped projections called villi line the inside of the small intestine. Villi absorb nutrient molecules. The molecules m the villi into blood vessels. Villi increase surface area.

The Liver Liver- located in the upper right portion of the abdomen. Largest organ inside the body. Role of the liver in the digestive system is to produce bile. Bile- molecule that breaks up fat particles. Gallbladder- bile comes here from the liver, bile is stored here. Bile physically breaks up food.

The Pancreas Pancreas- triangular shaped organ between the stomach and small intestine. In the digestive system, produces enzymes that flow into the small intestine and help break up starches, proteins, and fats.

The Large Intestine Large Intestine- last section of the digestive system. About 1.5 meters long Named for its wide diameter (about 6 cm). Contains helpful bacteria that aid in digestion and produce vitamins (Vitamin K). Absorbs water into the bloodstream.

The End After undigested food passes through the large intestine, it is eliminated from the body. Rectum- short tube at the end of the digestive tract where waste material is converted into a solid. Anus- muscular opening at the end of the rectum where waste material is eliminated from the body.