Your Body. How It Works. Digestion and Nutrition PDF Free Download
On the way home from her morning classes, Amy stops for lunch at a fast-food resturaunt. Amy is in a hurry and she knows the meal will be served fast and she knows the food is safe. The food may not be the tastiest in the world, or very good for her, but it will get her through lunch.Amy has eaten in this kind of place hundreds of times before. She orders a burger, fries, and a chocolate shake. She knows the burger and fries have lots of fat and salt that she does not need. She also knows the shake is risky for her. She has a form of lactose intolerance that sometimes results in abdominal cramping and diarrhea after ingesting milk products. But she is in a hurry, and at least she knows what she gets here; besides, she has been thinking about the chocolate shake all morning. After Amy eats her lunch, her body processes the hamburger, fries, and chocolate milkshake into nutrients her body can use. The digestive system processes the food people eat into nutrients for the body. The process takes nutrients in the form of food we can see, smell, and taste and reduces the food to small sizes that can be passed through the cells of the digestive tract and travel to places in the body that need the nutrients.Digestion starts in the mouth by taking a bite of food, chewing it, mixing it with saliva, and swallowing it. The food has been reduced to a smaller size, but still not small enough.