The Digestive System

1. The Digestive System

2. The Four Stages of Digestion • The process in which food is broken down, nutrients are absorbed, and wastes eliminated is called _________________ • The fours stages of digestion are: • ___________ • ___________ • ___________ • ___________ See page 70

3. Stage 1: Ingesting • Ingesting, or ingestion, means to bring food into the body. This is the starting point of the digestive process. See page 71

4. Stage 2: Digesting The Mouth • _________________occurs when your teeth and tongue break food into small enough pieces to swallow. • Each small piece of food is called _______. • _________________occurs when saliva begins to break down the bolus. • An enzyme in your saliva begins to break down simple and complex carbohydrates. • An _______________is a protein that speeds up chmemical reactions See page 71

6. Stage 2: Digesting The Esophagus • When you swallow, your food enters the _______________. • The esophagus is a long muscular tube that carries food to your stomach. • The bolus is pushed through the esophagus in a process called _________________ (c) McGraw Hill Ryerson 2007 See page 72

7. Stage 2: Digesting • Inside the stomach is gastric juice, which is very acidic. • The stomach walls are lined with ___________ to protect the tissue from being damaged by the acid. • An enzyme called _________, present in gastric juice, breaks down protein. • The bolus that enters your stomach breaks down into a liquid called ___________. The Stomach See page 73

8. Stage 2: Digesting • The first metre of the small intestine is called the ______________. • The pancreas adds enzymes that help break down the carbohydrates, protein, and fat in the chyme. • The liver produces _____________ which is stored in the gall bladder. • Bile breaks the globs of fat into smaller droplets. The Small Intestine See page 74

9. Stage 3: Absorbing The Small and Large Intestine • _______________is the process in which nutrients and water are absorbed by the small and large intestine. • The small intestine is covered with _________ to help increase the rate at which nutrients are absorbed. • The large intestine absorbs water and some minerals. See page 75

10. Stage 4: Eliminating • Any solid material, undigested by the end of the large intestine is called ____________. • Feces are stored in the rectum until they are eliminated through the anus. • Liquid and gas wastes are removed by your excretory system. • The main organs in your excretory system are your kidneys and your bladder. See page 76

11. Eating Disorders • _______________ • nervosa is a disorder when a person severely restricts what they eat. • Bulimia nervosa is a disorder when a person eats large amounts of food and then vomits or takes laxatives to get rid of the food before it is completely digested. See page 77 Take the Section 2.2 Quiz