I.The Digestive and Excretory systems

I.The Digestive and Excretory systems food provides nutrients that the body needs in order to grow. Before the body can use nutrients it must break down food into smaller parts Energy for life Digestion Digestion accomplished In the digestion system

II. How digestion works • A. Digestion involves both physical changes, such as the crushing of food by the teeth, and chemical changers such as the transforming of food by body chemicals called ENZYMES • B. Food goes into mouth and is crushed by teeth and broken down in mouth and stomach by enzymes then food is stored for use

III. The mouth and throat • Saliva starts to flow as a physical signal from your body that it is ready to begin the digestive process

IV.The beginning of Digestion • A. The Teeth tear and grind the food into small shreds or chunks • B. the Salivary glands produce saliva enzymes in saliva begin the chemical breakdown of carbohydrates, converting the starches to Glucose • The saliva also moistens and softens the fod for its transport through the esophagus • C. The food is swallowed and enters the ESOPHAGUS, a long, muscular tube that connects the mouth to the stomach

V. When you swallow a.The Esophagus is located next to the trachea or windpipe b.The trachea is the passageway through which air gets to your lungs c. The passages up to the nose are at the back of your throat d. Getting afood into your air passages could cause you to choke

V. When you swallow E. For that reason, two flaps of skin close airways when you swallow F. The uvula closes the airway to the nose G. The Epiglottis closes the airway to the lungs, as shown in figure 4.9 page 109

VI.The stomach and small intestines • A. Once the food enters the esophagus, muscles lining the walls of the esophagus contract and relax, moving food along until it reaches the STOMACH • B. The Stomach holds and processes the food for up to four hours • C. During this time the stomach’s strong muscular walls churn and mix the food • D. When this is complete food resembles a fairly thin soup called CHYME • E. The Food then moves to the small intestins

Liver and Pancreas

VII. The Liver • The liver is the body’s largest gland which secretes a liquid called bile that helps to digest fats • The liver also helps to regulate the level of sugar In the blood, breaks down harmful substance such as alcohol, and stores some vitamins

VIII. The Gallbladder • A. After the liver produces bile it sends it to the Gallbladder which stores this bile until it is needed

IX. The Pancreas • A. the pancreas is a gland that helps the small intestine by producing pancreatic juice, a blend of enzymes that breaks down proteins, carbohydrates, and fats • B. When food has been completely broken down, nutrients are absorbed through the walls of the small intestine in to the bloodstream

. Removing wastes

X. Removing waste • A. Body produces 3 kinds of waste • 1. Solid – waste body can’t break down • 2. Liquid – • 3. Gas – lungs get rid of carbon dioxide • Excretory system – gets rid of waste from body • Organs in excretory system – kidney, bladder,colon

B. The kidneys, bladder and colon • 60% of your body is made up of water • Most waste materials are dissolved in your body • The body sends a mixture of water and undigested solid waste into the colon (large intestine) • Most of the water is absorbed by the colon • The waste that is left is called feces

XI. Caring for your digestive and excretory systems • Eat balanced diet • Plenty of low fat high fiber foods • 6-8 glasses of water every day • Chew food slowly and carefully • Eat at regular times each day

I.The Digestive and Excretory systems