purpose of the digestive system

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Purpose of the Digestive System - the break down of food into nutrients digestion: process that breaks down food into small molecules so that they can be absorbed and moved into the blood - the blood transports the nutrients to all parts of the body so it can be used to make energy - unused molecules pass out of your body as wastes

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Purpose of the Digestive System. - the break down of food into nutrients digestion : process that breaks down food into small molecules so that they can be absorbed and moved into the blood the blood transports the nutrients to all parts of the body so it can be used - PowerPoint PPT Presentation

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Page 1: Purpose of the Digestive System

Purpose of the Digestive System

- the break down of food into nutrients digestion: process that breaks down food into small

molecules so that they can be absorbed and moved into the blood

-the blood transports the nutrients to all parts of the body so it can be used to make energy- unused molecules pass out of yourbody as wastes

Page 2: Purpose of the Digestive System

Types of Digestionmechanical digestion: the breaking, crushing and mashing

of food- starts in the mouth when food is chewed- continues in the stomach when food is mixed and

churnedchemical digestion: large molecules are broken down into

nutrients using chemicals called enzymes

- starts in the mouth with saliva mixing with food- continues in the stomach with acids- finishes in the small intestine

Page 3: Purpose of the Digestive System

Digestive Tract- mouth: teeth chew (mechanical digestion) and the tongue

pushes food around - saliva breaks down food (chemical digestion)

- esophagus: muscular organ uses peristalsis: wavelike movement to squeeze food to stomach

- stomach: muscular baglike organ that continues mechanical and chemical digestion - creates a soupy mixture called chyme

- small intestine: chemical digestion is finished here; food has been broken down into nutrients, which are absorbed into the blood

- large intestine: main job is to absorb water from undigested food mass - undigested materials become solid waste (feces), which is stored in the rectum and is expelled through the anus

Page 4: Purpose of the Digestive System

liver: makes a green liquid called bile, which is used to digest fat

gallbladder: stores bile produced by the liver

pancreas: makes materials that neutralize the acid in chyme

and further chemically breakdown proteins

Additional Digestive Organs

Liver

Page 5: Purpose of the Digestive System

Digestive Diseases Heartburn: results from backflow of

chyme from the stomach into the esophagus, which causes a burning sensation in the chest or throat Gastric Ulcer: an open sore on the stomach lining caused by bacteria Colon Cancer: affects part of the large intestine and is caused by cells dividing uncontrollably to form a tumor Constipation: body does not get enough fiber, water or exercise so the feces become dry, which makes it hard to get rid of the solid waste Diarrhea: indigestible food moves too quickly through the large intestine, so water is not removed and solid waste becomes a liquid