Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? Copyright © Houghton Mifflin Harcourt Publishing Company 1

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? What Goes In... Food travels through your body until all the useful parts are absorbed. Food travels down the esophagus, a long tube that begins in the throat. The stomach is a muscular bag that mashes food into a liquid and mixes it with digestive juices. The food then passes to the small intestine. Copyright © Houghton Mifflin Harcourt Publishing Company 2

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? What Goes In... The small intestine is a long coiled tube that digests food and absorbs nutrients. In the large intestine, water and minerals are soaked up, leaving only waste. Solid waste passes out of your body. Copyright © Houghton Mifflin Harcourt Publishing Company 3

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? What Goes In... Identify the esophagus, stomach, small intestine, and large intestine in the image below. Copyright © Houghton Mifflin Harcourt Publishing Company 4

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? What Goes In... The liver makes bile that helps break large blobs of fat into tiny droplets so the fats can be broken down more easily. The pancreas makes juices that are released into the small intestine to break down fats and proteins to be absorbed by the body. The gallbladder stores bile from the liver and sends it to the small intestine only when food passes through. Copyright © Houghton Mifflin Harcourt Publishing Company 5

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? Food for Thought Nutrition information on a package label can help you make healthy food choices. The number of servings, calories, proteins, carbohydrates, fats, and nutrients and their daily recommended amounts are listed on the label. Calories are a way to measure how much energy your body will get from food. Copyright © Houghton Mifflin Harcourt Publishing Company 6

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? ...Must Come Out The excretory system rids the body of waste and keeps water and salt levels in balance. When nutrients are broken down, waste products are made. The liver converts ammonia, which is very toxic, to urea, which is less toxic. Your body releases this as urine. Copyright © Houghton Mifflin Harcourt Publishing Company 7

...Must Come Out The lungs are also part of the excretory system. Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? ...Must Come Out The lungs are also part of the excretory system. Your body produces carbon dioxide as a waste. Carbon dioxide is released by your lungs when you breathe out. Copyright © Houghton Mifflin Harcourt Publishing Company 8

...Must Come Out The Urinary System Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? ...Must Come Out The Urinary System The urinary system filters the blood and rids the body of wastes as urine. The kidneys are organs that remove waste from the blood. Kidneys also help to conserve water and keep the amount of salt in the blood balanced. Copyright © Houghton Mifflin Harcourt Publishing Company 9

...Must Come Out The Urinary System Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? ...Must Come Out The Urinary System Urine collects in tubes called ureters that move the urine to the bladder. The bladder stores urine until is released. The urethra is a small tube that moves urine from the bladder to outside of the body. Copyright © Houghton Mifflin Harcourt Publishing Company 10

...Must Come Out Describe the movement of waste in the urinary system. Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? ...Must Come Out Describe the movement of waste in the urinary system. Copyright © Houghton Mifflin Harcourt Publishing Company 11

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? Chemical Messages Hormones are chemicals that carry messages through the body that result in growth and different changes. Groups of cells called glands produce hormones. Glands and hormones make up the endocrine system. Copyright © Houghton Mifflin Harcourt Publishing Company 12

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? Chemical Messages The pituitary gland, located underneath the brain, produces hormones that tell other glands what to do. It also releases growth hormones. The thyroid produces a hormone that goes up when you need energy and goes down when you have enough energy. The adrenal gland, located above each kidney, produces a hormone called adrenalin. Copyright © Houghton Mifflin Harcourt Publishing Company 13

Unit 3 Lesson 5 How Do Our Bodies Digest Food, Remove Wastes, and Send Messages? Chemical Messages The pancreas produces a hormone that controls sugar in your blood. When the amount of sugar is high, the hormone insulin is released. When your blood sugar is low, the pancreas stops releasing insulin. Copyright © Houghton Mifflin Harcourt Publishing Company 14